Just to contradict what everyone else has been saying :
Auto flowering cannabis plants, from what I have experienced, need care and attention to avoid stressing during the early stages of growth. Once they hit flowering, however, they are rather the same as photo-period plants.
From the auto's I just finished, all were trimmed to an extent. I removed lower growth which was useless even for popcorn buds, and any fans that were in the way of the buds. Auto Anesthesia, the biggest yielding plant, was stripped of all but little sugar leaves for the final three weeks.
I have ran a couple of experiments on defol and find it to be neither here nor there really. If it's stopping a bud growing, I will remove it. If it's not in the way it stays. Removal of excess growth indoors will also help air movement, thus reducing pests and diseases.
Up to you my friend, but I can't see a fan or two causing any problems
