i used to be one of those " dont touch any leaf during veg or flower" kinda guys, but after reading countless articles and post on the subject, and from my own personal experiments, i now agree with both of the above posters...if its in the way of buds, or yellowing and looks like shit, i take them off...ive never removed more than 30% of leaves in flowering, so i cant comment on anymore than that....but at 30% removal, the plant showed no ill effects, compared to the other untouched plants....