This would work - in case of getting a concentrated DMT-juice.
The DMT and other alkaloids are already present in the plant as their salt form - this is the natural occuring form, which will automatically form under physiological conditions of the plants. Therefore you can already dissolve them in pure water. Mimosa Hostilis may work less good, as it is the bark that contains the actives, and leaf material can be extracted with just water much faster.
You would just maybe get a reduced yield, as acid can further increase the dissolving process and also help to break apart plant cells in order to accelerate the uptake of any soluble components.
By doing a longer cook you may compensate for this, I think I read somewhere that the tribes of the Amazonas and Peru may cook their Aya over the course of even days, not only hours.
Then you could indeed concentrate it down. But you would never get a smokable mix for 2 reasons:
1.) The water will leave back a slimy residue, which would only get completely dry under a very big heat. This will then be everything that got dissolved by the water and only a small amount of this will be DMT. If you load leaves with material - and I would say 200 % of the plants weight is the maximum, again only when using pure DMT, as it *sticks* to the plant material when creating changa - you would only have a very small amount of DMT, as the mixture contains mostly other stuff.
2.) As you can extract it with regular water because of its already present ionic salt form, the final slime will also contain salt form DMT. This form has a boiling point of at least 100 or even 200 °C higher. You would never be able to smoke or vape that stuff. You could easily reach that point with a lighter, but all you would get is harsh black tar and products of combustion, which nobody would be able to hold in his lungs. Again even if you could, it would be too less DMT inside, as it is also filled with inactive material :/
Therefore the only way to handle this kind of slime would be to drink it, but then you would not even need to reduce the volume. So better just use leaves containing DMT, like Chaliponga and Chacruna and drink the tea without reducing. If you want changa, then this will not work that way :S