[EricH]

That's just it, Chris. A custom pneumatic inflating arm to raise the hook, powered by the air from the compressor, was specifically declared to violate multiple pneumatics rules by the GDC. http://forums.usfirst.org/showthread.php?t=14703

Now what I'd like to know is, how did the team in question inflate their balloon? If they did something like the above proposed design, then they were most likely in violation of the rules. Otherwise, it's an open question.