I've been involved in martial arts for 18 years now and pencak silat for a good portion of those and it's interesting to me that people still look for the "one size fits all" solution to martial arts. Over and over and over I see new iterations of the same old idea that somehow by studying this super secret special martial art you'll get what you need. Furthermore, you can learn whatever the "magic" system is in 20 or 30 hours or whatever and you'll be able to do it...Umm....sorry folks but I'm not buying.
I do believe that most good teachers have something to offer and can teach you a lot. You should respect what they offer and study it wholeheartedly but don't expect to become invincible. It's not going to happen. The best anybody can hope to do is bring their training to the fight. It's not easy in diverse situations where your life or your welfare is at stake.
In my opinion, and that's all it is, invest in the long-term training of skills and attributes that will show up when you need them and in ways that you don't necessarily train. You need adaptability and versatility in your training over techniques and methods.