Seriously, if we're comparing those two players in terms of the value they can bring to a football team, Tebow has a clear advantage.
If we're viewing both Tebow and White simply as read-option specialists to serve as insurance policies while Robert Griffin III recovers from offseason knee surgery, and if we're in agreement that Griffin is the starter and Kirk Cousins is the backup, then there's little reason to believe that Tebow wouldn't be an upgrade over White on the quarterback depth chart.
While neither should be considered a starting-caliber quarterback at this point, Tebow has won in this league. He's completed big throws in big games, while White has never completed an NFL pass. Even in college, Tebow was far better with his arm.
Tebow is also more versatile. Kyle Shanahan could utilize his big frame and skill set in a variety of ways, while White is simply a run-first quarterback, maybe a return man. He's also been out of professional football for three years, unless you count a stint with the UFL's Virginia Destroyers.
The Redskins won't likely go down that road, even if Tebow comes cheap and would be an upgrade over White, mainly because they—like most teams—won't want the attention that inevitably complements that sort of move.
Besides, Tebow wouldn't favor a situation in which a roster spot is far from guaranteed and a starting spot is completely out of reach.
That's a shame, though, because Tebow may not be a good quarterback, but he has the ability to be a damn good football player.