PE=Pectic Enzymes?
If so, i agree they are great. I use the formulated ones, ie Lallezyme EX or EX-V and I'm 100% sold. I've tended to use the prescribed, normal, recommended amounts. For sure, the color and flavor extraction is better. Much better. I don't know what would happen at higher doses.
It would be interesting to see a fermentation done with say 4X the recommended amount of enzymes and see if that made things better or worse. It may be a kinetic thing where the recommended amounts, already do 100% of the benefit.
I'm drinking a 2018 Primitivo I made tonight just to see how it's going. It got Lallezyme EX, and some wine-stix oak and I have to say it will be good in a year or two! Right now it's still pretty big in the tannin department. But it's good. It seems if anything, the enzymes would make the wine take longer to age to perfection, due to the higher tannin extraction.