Consider the fact that you were going to do two different 4 month sessions. One was a bulker, and one was a cutter. In which session would you feel training 6 days a week (hitting one bodypart twice a week while the rest of your muscles just once, rotating each week which bodypart gets hit twice) would be more optimal the 5 days a week(one bodypart per week)?????

Consider the session and which one you feel would require your muscles to rest more. Would it be when you are trying to put on the most muscle possible during your bulker, or would it be when you are cutting so that training the extra day a week helps with the fat loss and the increasing of the metabolism. Please, dont just consider those factors. Introduce as many as you want.

I know its not the the question of all questions, but a good training buddy of mine were discussing this for some time today at the gym. dont ask me why, we just were.