Originally Posted by
waters60
Define “ most users “. Think of HR as a metric of what you have been doing and PM as a metric of what you are currently doing. Let’s say you are riding up a 1/2 mile hill with varying gradients. As you start up a steeper pitch and want to be sure you are either not going too hard or not hard enough HR is worthless. By the time you are done with a 50 or 100 yard stretch HR may be reflecting what you had just done but will have offered no feedback while doing it.
That's sorta true. One can watch the rate of HR rise, which is also good information. The HRM will tell you about your more or less average effort, which is still good information. HR will also tell you things that power does not. I trained with just HR for 25 years, didn't get power until late '19. Training with power has made it mentally easier, but I don't think it has had any great effect on my average speed on hilly rides.