It's great to read informative and thought provocative threads again with participants that are in disagreement but which hasn't deteriorated into an exchange of personal jibes.
This is one area that is still unclear in my mind - "Is HR a good parallel measure to power".
Accepting that HR is affected by a number of external influences let's leave them out of the equation for a minute ...
I think Bikemax raised the fact earlier in the thread that pedaling at different cadences but at a steady power output elicits different HR responses.
Some cyclists are suited to lower cadences while others are higher revving - surely HR has some part to play in determining what the optimal cadence is for individual cyclist. For example, if you are outputting ftp ideally you would want the HR at threshold too? Again, ignoring the other factors for this case.
This may not be an issue for well trained or experienced cyclists but I have been cycling for only 3 years now (using power for 2) and in reviewing my data I have seen my "optimum" cadence gradually drop as I have ignored HR more & more. I'm not convinced that this is a good thing 'cause when it comes to race time I naturally tend to rev higher and get dropped (often) not when I am outputting more power than I can sustain but when my HR is above threshold for too long.
The theory I suppose is that I should determine what my real optimal cadence is and train and race to that in conjunction with power. So there is at least one other input in addition to power.
The reason I use power is cause I believe that is much more of a scientific measurement than HR so I am not inclined to go with the idea of "self-selected" cadence. In my case anyway, this is far too a subjective.
The question really is whether HR is too unreliable to be used as an input to determine optimal cadence at FTP.
But for the record HR is definitely is not a better tool than power!
Maybe not related to this topic but the other thing that pure power measurement does not explain adequately or account for is why are there different "types" of riders i.e. climbers vs sprinters for instance.
If 2 riders have the same power to weight (one is a big dude and the other is a small dude) then you would expect that they should be able to climb the same but this is not true. I can understand why they don't perform the same on the flats or where the force of the wind is a factor but climbing??