Platz never trained for strength. Don't use the exception to prove the rule.
One thing that most intelligent people in lifting push is doing what you suck at. If you suck at reps, how would you not benefit from getting better at them? Would moving your 5 rep max up 30 lbs make you weaker?
Were you just hitting singles on singles or something before?
I was doing 10 rep maxes and gained 60 lbs, however now I am trying to bring up my 1rm by slowly adding weight and waiting until I stall out. 5/3/1 works fantastically for my situation.
It allows me to hit all kinds of rep ranges, maintaining my high rep goodness, and starting to move me toward heavier singles.
Again, Platz is not a powerlifter, and he is a freak of nature/outlier. Look at all the other 5/3/1 success stories.
I promise that eventually, you will stall on 5/3/1. I can almost guarantee that if you are eating, you will be stronger when you do start to grind/miss reps.