Marynowitz said that after working out the quarterback this offseason the team noticed improvement in Tebow's mechanics, per NFL Media's Aditi Kinkhabwala, who was on the scene in Philadelphia for Thursday's news conference.
"We worked him out and we saw improvement from the last time we saw him, had exposure to him live when we played New England when they practice here," Marynowitz said. "When we worked him out, we saw a great deal of improvement with him."
Marynowitz added the Eagles "had had some conversations and some discussions, and we felt that it was an opportunity to bring in somebody who could compete for a spot," per Kinkhabwala.
Marynowitz's evaluation meshes with what personal quarterback coach Tom House told NFL Media's Albert Breer after working with Tebow the past two years.
Marynowitz stressed that the Eagles view Tebow as a quarterback and that no roster spot is guaranteed.
"We've got 68 players that are on our roster right now," he said. "Tim is one of 68 so he'll have an opportunity to compete for a roster spot here. ... His role will be determined by his performance. We're excited that he's a member of the organization, and we're looking forward to him competing."
One specific area the signing could make sense is Tebow's use as a two-point conversion specialist. The NFL is considering a rule change to the extra point, which could enhance Tebow's value.
"If that (change) does come to fruition, and there's a role there, depending on his performance, that may dictate if he has a role in that capacity," he said.
If Chip Kelly can find value in a third quarterback -- which on most teams is merely a low-level insurance policy -- the Tebow signing is worth every penny for the Eagles.