I find it;s best not to trim fan leaves at all, especially if they are healthy and green. The only time I find to remove a fan leaf is when it is dead and is no longer useful, other than that, nah.

Like people have said, it stresses out the plant. Also, during flowering, the plant uses its stored energy that are within the fan leaves to create buds. Less fan leaves=less energy for buds which can = less yeild.

BobBong is right, tie or tuck the leaf/leaves instead

Be nicer next time. We are all learning in one form or another, and to single out one another is not respectful because after all, you're a newb too.