I've been thinking about this over the last couple of days....and it worries me. Within BJJ, after the first few UFC's, everyone was searching out BJJ schools. I'm afraid the same may happen with Systema. Reason being...people with bad hearts learning these methods could be very dangerous. In the Russian Mafia, there are people that are former Spetznaz, trained in Systema and referred to as "The Perfect Killers". Does this concern you guys as well? There is so much information shared through Vlad's videos that it is possible for the not-so-grand type of person to be able to pick a lot up.