The Philadelphia Eagles, already this offseason's most scrutinized team because of the whirlwind of moves being made by head coach/czar Chip Kelly, just became even more fascinating. Kelly added Tim Tebow to the roster, which already has three quarterbacks.

Tebow, 27, hasn't seen regular season NFL action since a fruitless run with the New York Jets in 2012. He will begin his Eagles tenure as their fourth-string quarterback. Here are five reasons why this signing by Kelly is a foolish flight of fancy.

Tim Tebow Just Can't Throw The Ball

Tebow may have been a Heisman winner in college, and one of the NCAA's greatest-ever stars, but most of that was on the strength of his rushing ability. There is no questioning Tebow's prowess as a pure athlete. He is a big, powerful player and can certainly make an impact on a game. As a quarterback though, he's lacking.

He's completed less than 50 percent of his passes as a professional, and his 2011 Total QBR was an unhealthy 29.18. The 2011 season represented Tebow's largest sample size as a starting quarterback. Handing Tebow the keys to an offense requires changing the entire offense to suit his skillset-and hide his inability to make plays with his arm. Kelly just traded a competent NFL passer and a high draft pick to acquire Sam Bradford. It's safe to say Bradford and Tebow are going to require different playbooks.

Poor Mark Sanchez

Tebow is reunited with Sanchez, the Eagles' backup quarterback, whose life was made very difficult by Tebow's arrival with the Jets. Rex Ryan fatefully tried to implement special packages for Tebow to give opposing defenses another element to prepare for. The move largely backfired though. The Jets didn't trust Tebow to throw the ball, and his forays only served to disrupt any rhythm Sanchez was developing.

While Tebow's production should relegate this signing to the heap of deals that get made with no attention paid, Tebow comes with a large segment of fans that believe he should always be on the field. Those fans will make themselves heard if Bradford struggles or gets injured, and Sanchez battles turnovers.

There's No Help For Tebow If He Gets The Call

Tebow did have some success in the win column with Denver, largely because they committed heavily in the run game and limited Tebow to deep heaves. While he hasn't shown any accuracy in college or the pros, Tebow does possess good arm strength. He showed that in an overtime playoff win against the Pittsburgh Steelers in 2011, when he connected with Demaryius Thomas for an 80-yard, game-winning score.

In Philadelphia, there is no Demaryius Thomas. Jeremy Maclin was Philly's top pass-catcher last year, and this season second-year man Jordan Matthews projects as the lead dog. If Tebow becomes a major player in this scheme, his receivers won't be able to pick him up and this offense might sputter.

His Versatility Is Overrated

The idea of Tebow as an "athlete" that can be deployed in multiple roles besides quarterback is foolhardy. Sure Tebow may have the athletic ability to make plays as a tight end, or even as a linebacker, but he's trained to play quarterback. He has never spent time developing skills for those other positions, nor has he developed any instincts. A training camp and four preseason games are unlikely to prepare him for important regular season games.

Teams signing Tebow, are signing a quarterback. Why use him at tight end, when there are cheaper options littering the free agent market that are not only desperate for an opportunity-they actually play tight end!

He was cut by the New England Patriots in training camp before the 2013 season began. If Bill Belichick can't find alternate uses for a player, it's likely because he couldn't help.

He Makes The Other Quarterbacks' Lives Harder

Tebowmania is pervasive. Like in New York, Tebow's loud fans can make life hell for a starting quarterback without established credibility. Bradford may be a former No. 1 overall pick, but his long injury history and lack of success in the NFL make him no sure thing. Sanchez-well, most people have already seen that movie play out. If there are problems early, the Tebow fans will be out and about, making themselves heard, and turning up the heat in Chip Kelly's seat.