Without providing any specific source of information, I'd like to share a few thoughts that make scientific sense and could be plausible.
1- It makes sense that a deeper inhalation causes a larger portion of the THC (or oxygen for that matter) to be absorbed, because the area where absorption is possible is deeper in the lungs (you cant absorb THC in your mouth, throat, upper respiratory tract, whereas you get maximal absorption in the alveolis). In that sense, any smoke left in the upper respiratory tract is basically wasted, for that reason I tend to inhale some air after inhaling on the smoke. It's kinda like the air is 'pushing down' on the smoke and nothing will be wasted in my throat.
2- It also makes sense that a dynamic air flow will cause better absoption than the classic 'inhale and hold', because the THC in the smoke (or vapor) needs to be near the tissue to be able to pass through it, but if the THC is in a stable position in the middle of the alveoli, it will not be absorbed. Moving the smoke around could solve this problem. For this reason, I sometimes breathe rapidly in short gasps a few times before completely exhaling. This technique is null if THC is absorbed almost instantly though (I don't have the info here).
Just tossing some ides out, no articles to cite or anything obivously.