[EricH]

It is possible to violate the intent of a rule without violating any rules. Unfortunately, FRC does not have a rule like this gem from the SAE Aero Design rulebook: "The violations of the intent of a rule will be considered a violation of the rule itself." This led to a Q&A ruling a couple years back about something being a violation of the spirit, but not necessarily the letter, of the rules.

As such, while charging pneumatics with one battery and competing with another may be against the spirit of the rules, it is impossible to call a violation of the letter of the rules. (Also note that if it were a rule, it would be impossible to enforce.)