When you are at a high level… the gains are minimal… so why should you be doing ftp every month?
Possibly, because it’s the small changes that can make a difference
It’s not necessary to test that often when you get to a certain level and even the smallest of gains won’t make a big difference, +/- 5 watts on your FTP makes next to no difference to your zones.
Pretty sure most elite level riders test no more than twice a year.
I hired a coach but still use TR. He wants me to test only every 8 weeks. That works better for me at this point in my riding development.
If you are relatively new or still in that rapid FTP rise stage than testing monthly definitely makes more sense as you can quickly outgrow your FTP from a month ago.
I don’t think anyone’s really telling you you have to test every 3-6 weeks. From a plan creation standpoint it makes sense to start every phase with an FTP test. But no one’s telling you you have to do that if you’re at a point where fitness gains will be only marginal.
That said, I like keeping track if for no other reason than it’s useful to me to go back and see where I saw progression and where I didn’t. And the beauty of the ramp test is that it’s relatively quick and easy to recover from.
I’ve long felt that the FTP tests scheduled in the middle of the build cycle (for example) were generally unnecessary. I frequently substitute those out for something more in line with the plan (like VO2Max work in the case of build).