This is not an issue I have had yet, but I’d like to know how to deal with it when it first occurs…
Let’s say a Workout is too hard for me to complete so I lower the difficulty to say 95% and manage to complete it at this reduced level.
How would I rate it? Do I rate it at the 95% level OR do I say I failed it?
My understanding is you rate the work you did and TR will take care of the rest. TR will see that you had to lower the intensity so you just tell it how hard or easy you found the worout. Dont over think it.
If I have to modify the workout in any way (lower the intensity, take a break, skip an interval, etc.) and I couldn’t have finished it otherwise, I rate it “max effort” and let the algorithm lower the difficulty of future workouts if necessary.
I’m sure they did a podcast on it and the mantra was ‘rate how it felt and not to over think things’, the system will know you had to lower it. At an extreme if you lowered it 50% and it felt easy, that’s how you should rate it but the ai will know you lowered things by 50% to do so.
Same
I would mark it as all out
Depends on why I think I failed it.
If it was to hard, especially a new workout then yea go Max Effort.
If I have done the workout successfully before at this FTP but skipped lunch and/or had a hard day at work then I know why todays effort is to hard.
I dont think lowering the intensity for next time would help in that situation.
I agree with this. Its what I do too.
Always funny how there are 2 polar opposite recommendations already. 
As @HLaB said, just rate it how it felt! Always!
We’ll know when you adjust the difficulty.. 