I thought this was too interesting and too prickly a conversation to get buried in a thread about participation in racing.
My FTP is about 4.1 w/kg. It was about 3.8 last year. I raised it by working on almost nothing else, and by losing 5 lbs. With similar dedication over the next couple of years I think I could probably get close to 4.5, but I honestly don't think there is any physiologically natural way I could get much higher than that, with any amount of training or weight loss.
That's my race limiter. I know that if I enter a race with a climb longer than about 8 minutes, I'm going to watch guys ride away from me, no matter how tactically smart I am or how well I handle my bike. This year I have dealt with it by just not doing those races, which actually works very well as a strategy to keep me enjoying bike racing.
As far as I know, there's literally nothing I can do naturally to keep up with those guys.
I consider myself a morally grounded person, not a cheater, but I sometimes guiltily read about performance enhancing options, the same way I might occasionally click on a provocative looking youtube link. When I do, I find myself seeking out the downsides and relieved when I read about, for example, the bad things that happen when you withdraw from testosterone supplements. Phew, there's a reason not to do it that doesn't depend entirely on my own moral conscience.
I have riding buddies who I think are probably doping. It's all just speculation, but maybe gsteinb sees less of it, or less obvious signs of it, because he's already at the top of the sport. He doesn't see the guys who go from zero to hero in one off-season because of "training better" (even though I know what physical training they are doing). These guys magically break through physical barriers that are hard ceilings for me.
I have no idea how prevalent doping is in amateur masters racing, but I am willing to believe it's significant. Everybody has their own natural ceiling, and plenty of guys have ceilings that are way higher than mine. The top guys who have a legacy of winning masters races, I have no insight or opinion about whether they are clean, because I didn't know them before they were strong. It's the guys I do know coming up from the lower and middle echelons, whose ceilings seem far too dynamic, that I am more cynical about.
A lot of the cynicism comes from very easily being able to put myself in their shoes. Aging is a slow process of coming to terms with your own changing physiology, and every new concession to age can seem like a tiny defeat.