Lol , I never over wash , left to set up for 45 mins and a damp sponge for first wash with a joint swipe to remove any loose polymers, left to set for further hour before another damp wipe and buff off , dried dark grey instead of light grey , over wetting lightens grout with polymer residue , it doesn't darken it
..
I have no issues with my regular grouts and I stopped using bal for above issues yrs ago but seen as bal was purchased before I even quoted , then hey ho not my choice.
The patching wasn't noticed by customer but me being an OCD kinda guy, I noticed it.