I've posted quite a few times on TravelerKai's martial arts datasheet, but I don't really want to hijack that thread. This thread seems more appropriate.
BJJ changed my life. I'm not sure how else to say it. I'm 14 months in and addicted. For the first 6 months it was discipline. I didn't really like doing jits, mostly because I knew it was good for me and I was hopefully getting better.
From 6-9 months I'd say I started feeling the hook but it was still summer and I had a lot of distractions.
I had my first tournament 10 months in (last October), and leading up to it I really focused. I took a private lesson with our owner/blackbelt and we worked on side control and over-the-shoulder to taking the back. I drilled it over and over, finding and fixing my errors. I'd say the training for the tournament is what really lit the fire, because I finally had a sequence that I could use and dominate a few guys with.
Of course as a white belt, confidence in a move or sequence is quickly doused with reality and humbled.
Then x-guard. My dumb joke is, I used to say jujitsu changed my life...now I say x-guard changed my life. Really half x and x guard. We drilled it a bit, then had someone come in and do a seminar, and it was made for me. I've pulled it on so many guys who were on top and had me in half guard or mount. I'm sure I'm relying on it too much, but I'm perfecting it and it's really helping my bottom game.
I know my weakness. My weakness is leadership. I mean that as a personality trait of course, but also reflected in my jits. My coach the other day said I'm still a bit too tense. I told him "you mean on top, because on bottom I feel comfortable. I'm always confident in my moves that I'll get out of a bad spot, even if I won't". Yep. When I'm on top, he can tell because if I'm not in motion, there's a slight tense shake. There's a certain level of action, aggression, leadership that I don't have. That I'm not comfortable with. I'm more of a reactor, always have been.
This is why I started combat sports (I'm sure it doesn't only apply to jujitsu). Besides actually learning and working at something productive, I wanted to carry myself with more confidence. Of course what I didn't understand was that will be a humbling process. Develop confidence? No, discover your insecurities. Discover them in an area of life where you can't avoid them. You can't avoid working through them.
So besides perfecting x guard, my next goal is to become more comfortable in the aggressive position. I plan on grabbing my coach during open gym and going over some things.
To the point of the thread, anger and aggression aren't too different, and both are reflected in leadership and action. Jujitsu, or any combat sport probably, is a great way to discover the importance of these motivating factors.
Edit: One little story. We had this short but really stocky (PEDs?) aggressive black dude in the other day. I rolled with him, and he was tough, a real fighter. More of a fighter than a jujitsu guy...his jits sucked. But it was cool because he was digging his fists in, palming the face, doing little slaps. Nothing harmful or anything, and I told him keep it up. Keep us honest to fighting. He was really trying to piss me off, and for most of the roll he was giving me trouble. No worries, I just slowly, inch by inch moved into my position, then bam, grabbed x guard and swept him so hard. His aggression made him fall hard but scramble to get up. Nope, I wasn't having that. I went right at him and kept him down. It was a good exercise in "this is why I do jits".