One reason for my lack of being the arm-bar-ee is that I was so often the arm-bar-er . When you have been setting people up for an arm bar a thousand times, you recognize when you are falling into that soon-to-be victim trap yourself in time to get the hell out of it.
As I have been known (about a thousand times) to yell at people
"In the middle of the match is one hell of a time to try to be thinking of a plan."
Here are a few ideas on arm bar escapes.
First of all, I can think of six different ways to escape an arm bar and this is just off the top of my head sitting here drinking cognac at 1:30 in the morning.
1. Stack them
2. Forward roll
3. Twist out
4. Drive your elbow to the mat
5. Stand and lift (last resort and the worst of the bunch)
6. Curl them (only works if you're really strong but I have both done it and had it done to me)
You young, non-cognac-drinking people at practice at 7 pm ought to be able to think of more than that. Let's hear them!