He may or may not be experienced. The point is that inexperienced pilots will tend to over control the plane, trying to correct for everything the plane may do in the air. Experienced pilots tend to trim immediately and correctly, then let the plane fly without forever moving the sticks trying to correct all the time. This over use of the sticks uses up RX battery capacity faster than if the pilot uses the sticks less.

I've been using 5 cell 1200 mah NiMH's for my receivers. In my bigger planes, the expensive ones, I use two batteries.

CGr.