I don't understand how these experiences can, as you say, move us away from the comfortable comfort zone and show us all the "false" belief systems that one has accepted as true.
I can't say that I understand 'how' this happens either :) ...... I guess I experience it as a kind of contrast in that when I am immersed in belief systems, I do not know that I am, and even if I have cleared various belief systems in the past, there will still be some....right? So the 'contrast' is a kind of 'stepping outside' so that there is that possibility of a view on what was previously hidden. I find that there is a 'larger perspective' made available and this highlights various aspects of 'comfort zone' or 'belief systems' that are out of alignment.
Perhaps it's a bit like walking down a dark alleyway with lots of dog shit (the belief systems we step in coz we don't know they are there) - but with perspective, one discovers where to put one's foot down and where not so as to avoid discomfort and a mess :D.
......and on to the second part:
and do you really think that through the use of mushrooms we can understand our inner space (it would be magnificent)? and why can't we do it even without them?
Mushrooms are tools in my opinion - they don't do the work for me, but they facilitate vision. This vision (understanding of personal space) is entirely possible without shrooms - I'd say that 'evolution' takes place when in 'normal' states the 'higher' visions are integrated into everyday life (which is then in turn 'uplifted').
A meditation practice combined with a resolute intention to 'enquire' (explore) the workings of the inner self *without any external 'tools' is, in my opinion, a very solid way of proceeding. It's just that, for me, tripping has provided a lot of insight into this process.
For me 'healing' (understanding myself at a very deep level) is not dramatic as such but matter-of-fact, ongoing and evolutionary - as well as revolutionary :)