
 Originally Posted by 
GearHeaded
					 
				 
				you are correct in that if your coming off of a cut and at low body fat that that is an optimal time to put on mass, this is mainly because your so insulin sensitive at that point.
my point was that cutting down to low body fat is not optimal IF you still need to grow and get mass..  eg., If your 170 pounds and your goal is to be 220 pounds, taking months out of the year to get shredded and 8% bf is not ideal to reach that goal.
Also performance goes way down as your bf% get low single digits .  This is true of bodybuilders in the gym, as well as athletes (if a running back is 225 pounds and 14% bf , he is going to be performing much better at that BF then a shredded 8%)..  so again if you can't train heavy and optimally in the gym cause your super low Bf then this is not ideal for growth .
you can re-set your insulin sensitivity and illicit new growth (similar to post show) just by mini cuts and diet modification . there is no point to get to 8% bf (unless your goal is to step on stage , Imo)
One of the other reasons that higher levels (but not too high) of body fat can help with gains is that body fat is nothing but stored calories .. if your massing and trying to get in extra calories to put on size, but your super low body fat, then your body is not going to tap into these stored calories for energy . a calorie is a calorie wither its from food or stored body fat . being 12-16% body fat allows your body to tap into stored calories and will help you maintain a calorie surplus and thus grow AS WEL AS keep from using muscle as a fuel source (going catabolic) . 
your more likely to go catabolic and convert muscle proteins into glucose for fuel when your body fat is low. This is the opposite of growth, we don't want muscle protein break down. 
hope that helps