This is a good point. Generally speaking the larger the chainring, the less anti-squat. You can sometimes look up the AS profile on a site like http://linkagedesign.blogspot.com/
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You’ve eluded to the fact that bobbing does not matter so why would that matter?
Is the difference in bobbing relevant or not based on chain ring size? How is that not relevant?
As long as you both are going to keep the conversation topical and not have it devolve into another thinly veiled personal argument that has been going on in the XC Bike Thread for some time around lockouts, then yes, please continue to discuss the very real effect of charing size on the anti-squat values of bikes 
(the picture above was meant in levity)
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It’s not thinly veiled. If suspension bob doesn’t matter then why reference it? If the bob doesn’t matter then we can move on. If running a smaller chainring impacts the suspension bob and that matters, seems like we should discuss why it matters.
Cool, I’ll bite on this one.
The dynamics of chainring+antisquat value definitely depends on the type of suspension design and the overall antisquat curve combined with the type of shock tune and the gradient angle that plays into chain tension.
Generally speaking, the larger the chainring size, the lower the effective antisquat value for the same sag point.
However, this dynamic changes depending on the bike, rider, and terrain, so it’s not as simple as saying more anti-squat is better or worse. Similarly, what some folks call “pedal bob” in some scenarios may deliver more ideal traction in other scenarios when encountering obstacles that would otherwise upset the pedaling dynamics.
So, what I would say is that if you get excessive pedal-kickback from situations like trying to pedal hard over square edge obstacles while climbing, a larger chainring will likely reduce the pedal kickback and provide a smoother and less forceful pedalstroke at the expense of some anti-squat further down the cassette in faster downhill situations where you will still be pedaling.
This is most noticeable on single-pivot or linkage driven single pivots compared to dual-link designs like VPP or DW-Link. I had a Kona HeiHei for a short period of time that was an excellent technical climber and solidly efficient on steeper gradients, but suffered a bit on the flats given my choice of chainring. On the flip side, the SB100 that I have had less of a noticeable effect between the various chainring sizes that I’ve used.
(interesting graph from Linkage Design site I linked above)
(key visual note is around the anti-squat fall off rate between the single-pivot versus virtual floating pivot)
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It’s not really a “bite.” It’s an honest and sometimes intellectual discussion of the intricacies of suspension dynamics. I agree with your assessment honestly. The only thing I would add is that there is a pretty compelling reason to add a lockout when you sometimes need that smaller chainring upfront but don’t have the terrain with the square edge hits you describe. This way you offset the negative pedaling characteristics and retain the benefit of some extra gearing.
Much easier when the conversation doesn’t resort to parochialism.
Is there anyone left who favors a 2-by drivetrain? I have only one bike which is supposed to cover all types of riding. I cant run out of gears on level ground and I need my granny gears sometimes. I mind long derailleur cage more than a busy cockpit and I can still get to my dropper lever with ease. My front derailleur is very reliable and never needs any tuning. The front derailleur also allows me to drop to smaller cog to go down a gear while chain is under high tension when I come to a surprise climb. Moving to a larger cog in the back when the chain is under high tension is problematic…although perhaps not on newer bikes. I know everyone’s gone to 1-by drivetrans but I’m holding out for something with fewer compromises. But I do feel lonely in my 2-by club 
I use a 34 Oval and absolute black say…34T Oval chainring has an ovality of 32/36T and is best for someone who uses currently 33 or 34T round ring.
Gets my vote anyway!
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Not my intention. I thought your initial explanation was to be desired, that was what I was trying and failing to communicate. Not worth it, I should have just not responded. Not that I don’t value your input, your dissertation on kinetic energy wasn’t incorrect, it just (at least initially) wasn’t the most effective way to make your point (a point I actually agree with, lock outs are faster for certain sections, no arguing that) - should have just pointed to pedal bob right away. Anyway, I’m moving on. We’re on the same page. 
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It was hard for me to jump to Eagle because I really liked my 2x setup. I would generally run in the big ring and if I needed if I needed that little extra I could dump my gears by shifting up front to get over something then back to the big ring for most everything else. But I finally gave in and now I’m a convert. So I’m no longer really in your club but I do understand why you are in it
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Pretty interesting, the chart you posted has a very distinct difference between the two dual link, v single pivot bikes. It’d be fun to ride all these bikes back to back on the same climb.
Any examples you can come up with for the same bike with different chain ring sizes? This would really drive home the point.
Sounds like it works for you. I wouldn’t want a 2X for my mountain bike riding however I totally understand why some people do. Especially if I was stringing pieces of trail together with tons of road or even gravel. Hey, Shimano still makes excellent front shifting options, sounds like it’s working for you. I briefly considered 1X for my gravel bike but it was way too much compromise and I landed on a 2X set up. I use the bike on road and gravel so I definitely needed the range so I understand your decision. Rock on.
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I’m surprised by so many people running 34/36.
I’ve always thought of it as a combo of watt/kg, and steepness and duration of your race.
If you’re
6 watt/kg = 36
5 watt/kg = 34 or 36 depending on terrain
4 watt/kg = 32 or 34 depending on terrain
3 watt/kg = 30 or 32 depending on terrain
2 watt/kg = 28 or 30 depending on terrain
If you’re in Florida then run a 36.
This is assuming a 10-50 cassette. With 10-52 you can go up a size.
I have a 32-52 and it’s amazing. If I were to race on fire roads I’d go 34 but only if there wasn’t anything mega steep.
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This is pretty line with my experience. I’ve run a 28t and a 30t on my bike at about 3-3.5 W/kg, but I run an e*thirteen 9-46t cassette, so with a 50t gear in the rear, I would almost certainly run a 30 or 32 up front. My bike is also heavy by XC standards since it’s not an actual XC bike, so that likely factors in as well.
I love the summary, thank you. Would you suggest changes based on a rider’s preferred cadence at all or is that something that generally falls within the guidelines of these recommendations?
I’ve found with the standard Eagle setup the 34T is the best match for the East coast riding/racing I do. For most steep and technical climbs the 34-42 and 34-36 are the sweet spot for spinning and power, and my riding is dominated by those sections. It is definitely power based, as in the past the 32T felt great but as I’ve trained more and gotten closer to 4w/kg the 34T fills that spot.
I always keep the 50T saved for stupid climbs that you might as well walk. It’s just such a big jump, and feels rough if there is any dirt nearby so I don’t see how I could run it (or the 52) as a regular climbing gear. I run into a lot of these, most recently Lynn trail in the SM100 which @Nate_Pearson can attest to - Lynn Trail Mountain Biking Trail - Harrisonburg, Virginia
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You described my situation exactly. I like to get to my trails by riding and sometimes longish distances on the road. Once I am on trails I need gearing versatility and ability to make large gearing downshifts quickly. The XT shifting is good in that you can downshift more than one cog at a time, but droping to my 26T in the front is mechanically easier and more reliable when under high torque. And yes, shimano front derailleur is great.
A buddy of mine converted to 1-by and when we race on fire roads he tells me he ran out of gears (but is otherwise faster than I am). Why would an XC racer give up top end power, especially if they are more of a grinder than a spinner? Perhaps I overestimate the compromise of having to commit to a single size front cog…
If you really like lower cadence you could go bigger, but as a rule of thumb I like these recommendations.
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