The fan blew from behind the hives. We tried it with and without, with really seemed to help. It didn't hinder them at all as we had it set to come on at a specific temp and to just keep the air moving. The fence we have behind the hives really blocks any breeze that might be blowing. I think it was good to have the airflow around the hives.
Our thinking is, if things are cooler for them, they don't have to stop their other work to come out and expend a lot of energy to cool the hive. Our goal was to make things easier and more comfortable for them. It seemed to work really well.