Secret to long-lasting relationship: Shut Down or Close Lid?
On the software level his advice should be fine. The only difference could be battery life. Hibernation still consumes a tiny bit of energy and is therefore using the battery. Shutting it down completely should make your battery last a little longer which means that you're using slightly less recharge cycles. But let's be honest, the difference is near to zero - so don't worry about it. His advice should be fine.

A bigger concern should be your screen. If you clean it too often the reflective coating is going to get ruined. And if you don't use a keyboard cover you can ruined your screen/coating too.