Not sobering for me - I was never impressed by the quality of his volunteers in the first place. None of them explored DMT or ayahuasca themselves, they simply went to the hospital and got injected once or twice.
Spend 2 or 3 months getting the hang of extracting it and then put 4 or 5 years of devotion and exploration into it and you'll get a completely different opinion. It's like most things in life - you get out of it what you put into it.
I think one guy says "It didn't change my life" - nothing can change your life for you. It can simply give you a new perspective on life.