My general rule is to not remove any leaves until they are more than 50% yellow/dead.
Years ago I had 4 Armageddon autos going and I kept on removing one or two big fans a day. To help get more light to the rest of the plant. All at once I developed an albino condition where all the new "greenery" from the 4 plants wasn't green, it was pure white. The product was worthless and I ended up trashing a quarter lb. Lesson -- you can remove fans up to a point -- and when you reach that point it is too late. Ever since I have used my general rule and not lost any plants.
Good luck, BigSteve.