1. The fibers that we use in cycling are trained at different percentages of Vo2 max (no brainer), but the amount of time required to activate (but not necessarily maximize) each type is rather small. I find this interesting in terms of the trend towards going to a base that consists of tempo, FTP, and even vo2 work- the athlete spends more time at the percentages of vo2 max that will cause the maximum amount of adaptations for the three different muscle fiber types. The athlete will also utilize CHO more efficiently, so they will be more physiologically 'ready' when racing and a heavy build period comes.
2. Training at FTP might not be any better or worse than training at or around vO2 max/L5. In fact, if an athlete chooses the proper interval duration and frequency it can yield adaptations in less total training time. I'm not sure if one is ideal over the other, but for a competitive road cyclist it would allow one to train at the different intensity levels found in racing (L4 and L5, maybe a session at L6) while not increasing the overall training load if the proper amount of time is spent at each level. So a person can't only do 5m intervals to maximize the training effect, but can use them in addition to longer intervals to develop the same fibers in a different manner. This is interesting to me because I've seen interviews with some fairly prominent domestic coaches that never have athletes do a single 2x20 or even efforts longer than 10 minutes and have riders that win elite national titles- Evelyn Stevens is one that comes to mind immediately and CTS is another.
3. He doesn't recommend avoiding training FT fibers in base like most people commonly do and while I'm not sure of the conversion logic, keeping the fibers trained makes some sense. I see large changes in 1s and 30s power early in the year, but it never increases over an absolute level perhaps because I spend a lot of time getting back to where I was. I wonder if this is another reason why lots of elite and pro racers have a fairly easy time getting back to good form by racing and not using as precise of training programs because they make sure to never detrain a system completely and at the very least have trained for utilization of every energy system and muscle fiber type so that they don't have a gaping deficiency- they're 'ready' so-to-speak even if their training isn't optimized completely. An athlete that just rides with no goals or spends all their time doing one type of training isn't there and, as the article points out, it only takes a small amount of actual training to stimulate each fiber type enough so that adaptations are occurring.
Don't take me too seriously. The only person that doesn't hate