That’s not what they say at all. They say it’s good enough for most people, it’s “easy” to execute, and they emphasize that all of these field tests are estimated. Unless you’re testing blood lactate for MLSS, anything you do is an estimate.
The ramp test is in no way the most successful predictor of anything and anyone who tells you otherwise is selling you something… probably having to do with a ramp test. 
That’s not what they say at all.
It’s not? I’m not going to replay every podcast until I find the ones (plural) where they said this so fortunately, I found this…
Quotes from the above link (Coach Jonathan, TrainerRoad)
The Ramp Test assesses FTP and gradually increases power in one-minute steps until the rider cannot maintain the target power. It is the most efficient and accurate way to assess your fitness on TrainerRoad.
the information gleaned from the ramp protocol is more accurate than an FTP estimate based on a poorly paced 8- or 20-minute test.
Over 7,000 tests were completed during our beta period with the new Ramp Test, and hundreds of thousands have been completed since it was officially released.
Our data shows that riders who take the ramp test fail workouts at a lower rate than riders who don’t test or who use other testing methods such as the 8- or 20-minute test.
Quote from the my post above
They have said multiple times, the ramp test is the most successful predictor of being able to complete their workouts at a given ftp than any of the other tests.
There’s probably something to that to begin with but it’s also a little bit disingenuous - isn’t the main stated aim of AT that it will serve up sensible increases in workout difficulty in line with the athlete’s progression. Which is not really the same thing - of course you’re right that AT may take a couple of workouts to figure out what a rider’s real power @ VO2 max is relative to their FTP etc., but after that it’s about making sure the workout difficulty keeps pace with the athlete.
Not sure people buy TR because of the ramp…
TR offers a range of FTP tests and gives you the ability to manually set whatever FTP you like.
The reason they recommend it seems to be because of the above reasons… although obviously we’re just taking their word for it on the data front. When I started using TR I was doing the 8 minute.
As always there are many factors and assumptions for context, in isolation it’s unlikely to be a useful discussion.
Firstly - how high? How low? There is a tendency is some posters to think that any inaccuracy/imprecision is the end of their training success.
There is an implicit assumption that your ability to train from one day to the next is equal - it isn’t. So there is some variability in how your body will respond to different power outputs from day to day - I for one don’t know how much variability that is. I think it’s reasonable to think that’s more than 1% - a significant figure in most of these discussion.
What is the variability of the impact on the target audience? Casting my eye briefly over the list of posters in this thread I’m willing to bet it’s zero. Why? Because anyone who has done structured training for more than one season knows what a vo2max interval is like. You can’t tell me you can finish a set of 4min vo2max intervals at +5%W. And don’t give me that “I’m an outlier” stuff either! On the internet, we’re all outliers.
For complete newbies? Well I’m going to say there is - over a season - little impact to them too. People who have never done bike training before see their FTP sky rocket from their first FTP of the season, mostly because they don’t know how to push hard on the bike anyway so their first six weeks training is probably underpowered from a physiological point of view if not psychological. Point being their fitness improvements won’t be massively effected.
And…I’ve run out of steam for now, 
Long and short, this really isn’t as important as the level/intensity of debate makes it out to be. FTP is useful to training but it is not the most important factor.
Oh I know KM has/had a lot of airtime here and I’ve read all those posts, but this podcast was end of last year and it was that I was referring to. I listened when it came out and expected people heads to have come off in here the next day, like when DJ uploads etc, but nobody made a peep about it… 
When KM talks about his longer test protocol he says athletes MUCH prefer it and are happy to do it. I suspect thats (at least partly) because the work he has them doing ensures they have a good ‘feel’ for what FTP efforts are like and prevents the usual issue of people going out with their ego and blowing up after 5 mins and trying to hang on.
For reference, I did 5 and 20 min tests this week. I’ve done lots over lots of years. The 20 min test obviously hurts as you’re going over FTP and trying to hang on, but dial it down a few % and its not that much of an unpleasant experience and easier to finish mentally.
In the context of TR I also suspect that the fact most plans don’t really include many longer FTP intervals (there’s more recently but still not that many) that people just aren’t used to riding at FTP for more than a few mins at best, so FEAR these longer test protocols. It’s another philosophical difference between KM and TR as well - the first ‘good’ workout they talk about is ‘add 5 mins to your threshold intervals’. You dont see as much of that in TR plans as you do ‘add intensity’, which again appears as a ‘bad’ approach in the EC podcast. Different philosophies and viewpoints…
Its crazy how similar our minds all work
There’s a whole lot of qualifiers in there that you seem to have ignored:
“poorly paced 8- or 20- minute test”
“… who don’t test”
“… on TrainerRoad.”
Their set of data is uniquely TrainerRoad users. The Ramp test is easy to execute, easier than properly pacing an 8- or 20-minute test, particularly for athletes who may not have a good feel for MLSS or riding at threshold. I have zero question that the ramp test fits TrainerRoad and its business model very well.
So what those guys are saying is the proverbial self-licking ice cream cone: if your FTP is accurate, their workouts are more achievable. If you test, you’ll probably have a more accurate FTP than if you just enter a number that sounds good; and based on their data set of only TR users, the ramp test is fine. You write training plans that are based around a ramp test, then you come out and say, by conducting the ramp test like we tell you to, you’ll be better able to complete our workouts… that seems like the most obvious thing ever…
… but it doesn’t mean the ramp test is accurate or predictive of performance on anything but the ramp test itself. They implemented it because it’s something that doesn’t require coaching or experience or any semblance of ride feel to conduct and is reasonably accurate for about half of the population. In other words, it was good enough for their business purposes.
They don’t. As I said above, the ramp test fits their business model and their customer base well enough, that’s why they encourage it. But those facts make it neither predictive nor particularly accurate.
TR’s “data” is also self-fulfilling. People that over-test and burn out quickly will leave the platform after failing all those workouts. Does TR even count the riders that only lasted 1-2-3 months as part of the “data”?
Honestly, it’s hard to understand the not liking to test mindset. If one can bust out SS and FTP intervals, they can test once a month. It’s essentially another FTP workout.
TR probably needs a TTE test on top of the ramp as a validation. It would basically be a Kolie Moore FTP baseline test after the ramp. Take the ramp value and start the TTE test at 85%, in 10 minutes bump to 90%, bump to 95% after 10 more minutes, bump to 100%, bump to 105%, etc. A 30-40-50 minute sweet spot / threshold workout shouldn’t be a problem for riders. And most new riders wouldn’t make 30-40 minutes anyway.
I genuinely don’t understand these threads. Does actually knowing, down to a watt, exactly what your FTP is matter? No. Are you able to gauge whether your FTP is set close enough just by doing one over/under workout? If you’re the type of person arguing about testing protocols, I’d sure hope so. FWIW, neither the 20 minute test or intervals.icu give me a usable number. Way too high (except when intervals is looking at a ramp test… then it spits out the same number as TR).
What makes you think it’s way too high?
I count myself in the group who hates to test. There’s a lot of psychological factors - success/failure, expectation, doubt, etc. - tied up in the outcome. Irrational, for sure, but have been FTP testing for 10+ years and still have these sensations on test day.
Because I could never complete workouts at the numbers they give me. Especially intervals. My peak eFTP on there from this year was 284W, derived from a 14 minute climb. I’m significantly more fit than I was for that ride, and I’m training off of 250 right now. I did a 20 minute test around that time, and got 260… again, more fit now, and wouldn’t have been able to complete workouts with that at the start of this block.
I’ve been racing/training at a high level now for 18 years, I got into cycling my freshman year of high school and did the JR (raced abroad even), Collegiate and “adult” team thing ever since. When I had kids (3 years ago) I struggled with training, a year ago I gave up on both ramp tests and power numbers and went back to the classic HR zone training with as much consistency as I possibly can.
I can honestly say that this was hands down the best move I could have possibly made, im still doing well at races, hanging with my fast groups and just in general happy to never have to look at the “number” anymore.
I am a horrible FTP test taker in general and always hated it. I find now that when I am training and only watching HR numbers that its not a mental thing when im no longer watching power numbers… I.E im not getting pissed when I cant hold whatever watt for this interval for however long but instead just focus on zone x…
IDK, this is new to me and just wanted to share that.
I totally understand. Switching from the 20 minute test to the Kolie Moore Baseline test has totally changed my perspective.
With the 20 minute test I’d always start off a little too hard and by minute 15 I’d either have to back way off on power or fail. 20 minutes of 105% of FTP is tough mentally. The gently ramping nature of the Moore Baseline test is much easier to accomplish mentally.
TR could sell it as an “Adaptive Levels Validation” or something less loathsome sounding. Or just make it the first workout of a block and call it mandatory.
I’m just curious.
How many days/workouts did you fail before you decided the FTP was too high?
How did you rule out all the other factors that might affect your ability to complete workouts?
And lastly, how, and how long ago, did you establish your previous FTP?
I use heart rate. The protocol I invented is beyond reproach.
It’s not that I don’t like to test exactly, I just don’t really see the point in doing a test for something I already know the answer to - I can estimate my FTP to within a handful of watts just by the riding I’ve been doing. I do plenty of hard efforts to benchmark from as it is.
The only time I really test is when I know I am going to get a big bump and I want to feel good about myself shrug
End of discussion 
I don’t think anyone considers the ramp test perfect. But for people with little experience pacing a test it might be more precise.
But the main problem is people putting way too much value into a single number. Anchoring short and long intervals to the same number can never be perfect. Then there is also day-to-day variance of performance.