This is such an ongoing debate...yet still no 100% clear cut answer.

When I first started smoking, it was a 'fact' that holding it in longer got you 'higher'. I never even heard about the '99% instantly/3-5 seconds' until I came here. I have still yet to see any facts or scientific evidence to prove this, but I have seen many people on here say it...I don't get it...where did this come from LOL?!?

It's hard to say what the truth is really...I usually do 3-5 seconds if I have weed to go around, but if I only have like a bowl, I might do 5-8 just to 'make sure' I get high. I would never hold a blunt hit in for more than a few seconds though.

Anyway, in my opinion, instantaneous absorption is a little far fetched, but 3-5 seems to make more sense.