What SSOG is posing (as I understand it) is that in a 53 man roster, the Broncos have Orton as the only active QB, Tebow @ RB, and 51 other players. Should Orton get hurt in the first quarter, Quinn (the designated emergency QB) comes in and Tebow is still eligible to play. I don't think that's feasible, and would clearly be a work around.
I think when the season starts, there will be two possibilities:
[*]Orton, Tebow, and 51 other players w/ Quinn as emergency QB. in this case, if Quinn plays in the 1st three quarters, neither Orton nor Tebow are eligible to return.
[*]Orton, Tebow, Quinn and 50 other players. In this case, there are no restrictions, and it really doesn't matter if Tebow is considered a QB, RB, HB, TE, whatever.