A dozen doses really? Maybe the volcano bags are bigger than mine. The vapor would definitely get pretty dense at that point, condensation may be an issue - The bag is already opaque white when I vape 80+mg at a time.

I find that the age of my enhanced leaf greatly determines the vaporization efficiency - fresh enhanced leaf (1-2 weeks old) is still not completely dry and won't completely vaporize on the first bag, maybe 80-90%. Once the leaf has totally dried, the vaporization is much more efficient, and I usually have to lower my dose.

You can also save any partially-vaped leaf and throw it in the next extraction, or use some ISO to clean the bag and reclaim condensed DMT.

It's definitely my preferred way to dose, no fumbling with lighters or pipes, just inhale!