Doing more harm than good?- Cleaning a PCB

I've just been splashing alchohol all over my mixer's PCB's after replacing caps on various channels and scrubbing w/ toothbrush.
(99% and when that bottle got a little dirty w/ DC I switched to a 91% bottle I had)

I thought I'd ask though if I should take it easy or anything. I'm pretty liberal w/ the stuff and I get the board looking pretty clean, but I'm wondering about possible harm I might be doing.

Reccomended cleaning procedures?

Make sure the runoff is consistent and work your way from one side to the other, leaving behind the cleaned areas and not getting them recontaminated with runoff from another section.

There might be the odd case of a component's encapsulation dissolving, so watch for any signs of deterioration as you are going along.

You may want to avoid splashing into potentiometers since you may be removing protective layers of lubrication and exposing things to oxidation/corrosion.