Is there a maximum allowable team size? Or may teams be arbitrarily large?

We see that this year's Game Manual Part I has added the new definition "Team An official FIRST Tech Challenge Team consists of no more than 15 student Team members..." that was not in previous years' manuals.

Yet at some tournaments we have seen teams with many more than 15 on a team. For example, see the team pictures at http://www.lexrobotics.com/2bitsandabyte and http://www.lexrobotics.com/welcome-t...he-parity-bits. We note that very large team sizes provide those teams with substantial advantages in building, programming, outreach, scouting, etc.