Did a 20 minute FTP test today (self administered via TrainerRoad on my Kurt Kinetic Road trainer). Bumped FTP up to 249 watts from 242 and LTHR to 158 bpm from 152.
Of course, the question is: could I have gone harder? Here's the tale of the tape:
I can honestly say that I don't know. You can see how I ramped it up a bit there towards the end, but it was agony. I do know it was a good thing nobody was home at the time, I was making quite a racket between breathing hard and gasping loudly.