One of the things about being well-trained in a good system and then filtering it through experience so it is tight and (possibly more important) I trust completely what my body will do is that I can't really learn a new good system and even have trouble with good drills.
I can learn and practice crap all day. I don't as a matter of principle, I hate to waste time... but crappy stuff doesn't compete with good stuff in my brain. It goes in the worthless box or the toy box. But when I see a new system with an extraordinary instructor and great drills, it is hard to practice. If the drills are real enough, I do my stuff. I trust my body to get me out alive. To override it at this stage is to practice staring into the sun. It is a discipline, but it will not serve me when I need my eyes.
First noticed this with Mac. Not just an extraordinary fighter who understands both martial arts and violence, but an extraordinary teacher and a good man. It would be an honor to learn from him. But his stuff is too good and doesn't blend. It is close, but I work about four inches closer. My techniques won't work with his strategies, and visa versa.
If I had started with Mac as an instructor, I would be effective and happy. If I was a hobbyist, collecting two systems (not necessarily in the sense of a martial style, but in the sense of a strategy/tactics/technique/mindset package) wouldn't be a problem. As long as I was in a life where I needed clean reflexive action, trying to integrate (or separately absorb) two systems would be very dangerous. I like crosstraining. I like playing with anybody and everybody, but I am very picky about what I absorb.
Today was another day of meeting good teachers in good systems. Danzan-ryu. Kuntao. Mayhem. Whatever Tristan was doing...
Two insights from today, among many:
"I would never turn my back on an opponent."
"Then you have never fought multiple opponents."
"What it does is what it is." In one sentence he lays to rest the argument about what a particular move in a kata is.