Originally Posted by
mrflibble
Yeah I definitely should have phrased that part much more carefully. To clarify, I'm sure Will's "very, very heavy" 275 felt a different kind of heavy than his 475 (perhaps that was very, very, very, very heavy). I'm also sure he would be able to Perceive the difference between the two heavy Exertions and with that be able to relatively accurately estimate how many more reps he could do of each.
My main point was that just because the bar feels heavy or moves slow doesn't automatically make it an RPE 10
This is a very good question. Yes, you certainly can (to varying degrees) perceive exertion visually - but you cannot reliably rate it (on the RPE scale) visually. The only exception would be a coach who knows that particular lifter very well.
Which is back to my main point: RPE 10 can appear very different on different lifters.