[Jeff Waegelin]

Well, 3v3 is theoretically possible. You would, however, need at least 6 (12 would be preferable) Arena Controllers and radio channels to do so. 2v2 requires only 4 controllers and 4 channels. Now, a standard FIRST regional uses 8 controllers and 8 channels, but at IRI last year, I believe only 4 controllers and channels were used (probably for cost reasons). So, it's possible, but the organizers would need to rent more equipment to do so.

Of course, this is just from the controller standpoint. You would also have to account for an extra place to put the third alliance's controls, a place to start their robot from, and the scoring system. All in all, it just seems like a whole lot of work.