No.. the rested, motivated, 20min test x 0.95.. it's a waste of time because you're not going to get a value any more accurate than just using power you routinely do for 20 min intervals in training.. there is just no practical reason to take away from your training to do a formal test to determine FTP.. if you are going to do it you should do a 1hr test.. why not test the thing you want to test directly.. but even so.. it's overkill.. you don't need to know the number that accurately..
