Yes in the buggy, just got the E-Maxx yesterday.
The batteries weren't extremely warm after that and how would a short on some metal part affect the controller?
There chassis is made of CF though and the controller was shrink wrapped, don't know...
If you are talking about an internal short, that's what I think is most probable. Maybe it got damaged with the 7L and BEC when it thermalled regularly.
If you look at the picture there is some dirt on the caps and on other parts which I couldn't just brush off, it was somehow glued there. I cut most of it off with a pretty sharp knife.. After that I got maybe 20 minutes of run time until this monday.
Could something like that happen if the motor has a short?
Some other ideas were that the receiver lost connection and apparently that makes the controller brake pretty hard. That happened a few times after I resoldered the plugs on the warrior but only when I tested it lifted of the ground.
On the track it didn't do anything unexpected I think...