It's hard to choose one lesson from them all. Here's one or two that comes to mind right now.
As a kid I worked at a taco bell, The managers raved over what a good job & how hard a worker I was, I kept getting raises quickly & they at one point were agrivated that they needed a shift manager & I was the only one qualified for the spot but I was only 16 and couldn't be a manager at that age. I told my father that I couldn't understand what the big deal was as I was just doing my job? I stayed busy & kept working all the time, after all I was on he clock & they were paying me to WORK? He said son, there are alot of idiots & slackers out there. Sometimes all you need to do is just work & do a good job to look great compared to the idiots next to you. So go to work and thank the idiots.
(mildly related) Just days before I bought my 1st trailer to start my business, I had my wife have about 4 lawn care companies come give us an estimate on our house... 2 of the 4 told my wife they weren't sure they could keep the yard looking as good as it did when they came to do the estimate....? What the hell is that?! Thank you, idiots. I was glad to know my competition for this business would be as tough as the co-workers back at taco bell.
As far as fighting.... I was always taught to drop the biggest guy 1st. Get him out of the way. Useful advice that has been implemented many times.