I find it rather interesting that Tim Tebow is acknowledged, by everyone, as a non-starting caliber QB.
For his career Tebow has a QB rating of 75 over 14 career starts with a 17/9 TD/INT ratio, 2400 yards and 6.7 YPA. Additionally he has 989 rushing and 12 TD. That gives Tebow a combined 3400 yards (rounded) and 29 TD.
Here are 7 other "franchise" QB's with comparable/worse statistics last season.
Brandon Weeden, 72 rating, 14/17 TD/INT, 6.5, 3400.
Tannehill, 76, 12/13, 6.8, 3100.
Cutler, 81, 19/14, 7.0, 3000.
Sanchez, 66, 13/18, 6.4 2900.
Bradford, 82. 21/13, 6.7 3700.
Ponder, 81, 18/12, 6.1, 2900 (+253 rushing)
Even the prodigy, Andrew Luck, isn't substantially better with QB rating of 76, 23/18 ratio, 7.0 YPA and threw for 4300. He chipped in 255 rushing with 5 TD. That gives Luck 4500 and 28 TD.He has an extra 1000 yards over about 250 passing attempts (about 130 fewer rushing).
Then you have Vick, Locker, Cassel, Quinn who were all "starters" at one point or another last year.
I'm not saying Tebow is a good QB, but he produced just as well during his opportunity as a lot of other guys. However, I do not think that there are 30 QBs who are better than him.