RANT WARNING
Okay, I agree with a lot of what you said in this thread, but I’ve learned to never ever ever be guided by “my buddy did this and that” sort of argumentation. One well-known local age grouper here, who has once won Ironman Weymouth (in absence of a pro field) and has even attempted a 2-hour bike on a flat course, was known for training between 10 or 11 p.m. and 3 a.m. (A busy IT programmer, and a father). I thought it was OK for me to be finishing workouts at 11 p.m., I mean it had to be. Turned out, it wasn’t. I couldn’t expect good results from such a schedule, as 99% of athletes couldn’t. Same thing with the “broke 10 hours in an Ironman on 10 hrs/week of training” success stories - utterly meaningless to the general population. OK, RANT OVER 
My example, to illustrate how individual these things are: I’m half-decent on the bike, often finishing in the 10th percentile in short-course races and about the 20th in middle distance here locally. But my best 70.3 I rode at 79% of my “FTP” obtained in the ramp test. (Also it was the hardest I’ve managed to ride in my four 70.3s! Bizarre guy, me). It was a 2:30 bike (17th percentile), followed by a 1:40 run, so an okay run for my standards (21st percentile).