From Andrew Brandt of ESPN (http://espn.go.com/nfl/story/_/id/8143417/nfl-power-core-franchising-issue)

Q: What is the holdup in negotiations for the top ... picks in the draft? -- Lee in Minneapolis

A: .... The holdup may well be the teams' demand for guarantee offset language, meaning that were the player released and signed to another team, their obligation would be offset by the other team's salary.

This seems especially relevant to Dontari Poe and his percieved "bust" potential.