I agree, 10 min is WAY too much for break in. Your wearing out your fresh com before you even go out to run. Heres what I do for break in:
1) Do the normal stuff (clean it, new brushes, skim com)
2) I use my pulsar and run it at 3 volts untill I get a fairly solid amp draw. It should sound funny and the rpms jump up and down when you have unseated brushes, so mainly just listen and look to see if it's arching bad. It should have a nice smooth consistant sound.
3) I will then just pump it up to 4 volts for a few seconds and listen and watch again. If the Rpms fluctuate then they aren't seated all the way. Just bring it back down to 3 volts again and run it for 1-2 more min.
4) Make sure you have the brush hoods aligned, have fresh brushes/springs, strong magnets, and properly broken in bushings. With that you should be ready to go. My total break in procedure takes about 3 min total. 4 at the most, but I use super stiff brush springs and high silver brushes so taylor it to your needs.
-Sushi Boy