Impure spice would be doing it wrong, for sure. Who knows if some toxic chemical from the bark made it into one's spice? But to me, doing it right comes from doing the appropriate amount and ingesting it with proper technique. Burning it or inhaling too quickly could make a big difference in the experience. I really wonder if a 30mg dose would feel different if it was inhaled over a 90 second period versus if it was vaporized in a crackpipe and inhaled in one quick toke.

Being in the right mood also helps.

which toxic chemical from the bark? there isnt any... What can happen is people not drying dmt well enough and having traces of solvent, or not separating well and having traces of the basified liquid which are harsh to smoke, but there is no toxic chemical from the bark itself.

Anyways I agree with the necessity of ingesting the right amount, in the right setting, and not burning it.

Or you could say, it builds you character by subconsciously re-arranging mental contents.
Other psychedelics like mushrooms, ayahuasca and perhaps LSD (i trust you there) tend to give more clear ideas our egos can use as tools to better our existence.