Of course you would personally notice. But the parent was talking about the effect on muscles. And it has been long estsblished that 5-30 reps (perhaps even highter) will cause the same hypertrophy.

Obviously, for practical reasons the optimal range for each exercise will vary. For squat 5-10 is definitely better than 10-20 let alone 20-30. For DB side raises highter reps would feel better than the lower rep range.

> I feel like I would definitely notice if I went from 12 to 25 reps on any exercise I do.

To be clear, the implication is that 12 and 25 have different weights so they tire you the same amount. Do you think it would be a very strongly felt difference in that situation? What would the difference feel like?

You consciously notice of course, like what kind of argument is that. The point is the stimulus is the same for the body unless you change it by orders of magnitude, the study agrees that this is the same also.