I am not sure how long people hold their hits for, but a single lungfull held until you absolutely need to breathe again is sufficient to get all the way there. The idea that people need 2 or 3 hits often forces people to exhale plenty of good alks in their rush to get the hits done while hyperspace is creeping up on them.
If after holding a hit as long as you can, you can still think of taking another... go right ahead. Heheheh.
I suppose it depends on one's lung capacity, smoking method, admixture herbs (if used), general cardio-vascular fitness, and a host of other things. There are plenty of people who can't hold their breath for all that long even without vapor or smoke inside.
For those people, or the ones who prefer not to stress themselves with holding hits so long, there is always the balloon method.
https://www.dmt-nexus.me...aspx?g=posts&t=25477Welcome to the Nexus Giantchief. May the spice be kind to you.
"Curiouser and curiouser..." ~ Alice
"Do not believe in anything simply because you have heard it. Do not believe in anything simply because it is spoken and rumored by many. Do not believe in anything simply because it is found written in your religious books. Do not believe in anything merely on the authority of your teachers and elders. Do not believe in traditions because they have been handed down for many generations. But after observation and analysis, when you find that anything agrees with reason and is conducive to the good and benefit of one and all, then accept it and live up to it." ~ Buddha