Oh agreed, if Manning is healthy and gets up to speed with the offense/team, sure they'll be potent eventually.
Tebow is fucked in the sense that he'll no longer be on a team that has to justify taking him in the first round. Fox had to simplify Denver's offense just to deal with Tebow's skill set or lack thereof. What other team is going to do that, especially with a lot of these bad teams that have new coaching staffs? Will any coach want to scrap plans they've been working on for weeks/months just because Tebow is coming to town?
Jacksonville just signed Chad Henne, who isn't a good QB but can be solid with decent pieces around him. Miami has Matt Moore (who had some decent games last season on a shitty team) and David Garrard. So even if Tebow goes there he wouldn't be favored for a starting spot. Fans are going to start a ruckus and demand he start wherever he goes. Nor will he have a good OL, defense, or receiver core to bail him out. So the Tebow myth will basically die over the next couple seasons unless he significantly improves