What is Percy Harvin upset about?

EDEN PRAIRIE, Minn. -- If I had a nickel for every NFL player I've heard express some sort of offseason dissatisfaction, well, I would have many, many nickels. So I won't immediately launch into a tizzy about Percy Harvin's unexpected threat Tuesday to skip training camp if several unspecified issues aren't resolved by then. Historically speaking, these "conflicts" get worked out more often than they lead to a holdout, especially when a player is under contract and thus subject to fines for every day missed.

What makes this situation unique is neither Harvin nor the Vikings offered any hint about the nature of the issues.

"Just haven't been real happy lately," Harvin said. "So we've got a couple things to work on." (Full transcript here from 1500ESPN.com.)

Harvin had a career year in 2011, catching 87 passes and finishing with 1,312 combined rushing and receiving yards. He has two years remaining on his original rookie contract. Does he want a new deal?

"I don't get into specifics," Harvin said. "Just overall haven't been real happy. But we're here. Hopefully, we can get things worked out and go from there."

By implying there are multiple sources of conflict, Harvin opened himself up to questions about his happiness with a rebuilding roster and, perhaps, his role in an offense that -- despite his production -- took him off the field about 42 percent of the team's snaps last season.

This much is clear: Harvin will avoid up to $60,000 in fines by reporting to minicamp, but he won't be doing anything on the field. Coach Leslie Frazier attributed that decision to caution with Harvin's shoulder injury, but it's worth noting that Harvin participated in football drills during one organized team activity (OTA) this offseason before skipping the rest of those practices.

There have been no reports of a setback, so if you wanted to call Harvin's current situation a passive holdout, I wouldn't argue with you. Why else would he not be participating this week after doing so several weeks ago?

In many ways, a contract dispute would be the easiest for the Vikings to broker. If Harvin has any deeper issues with the franchise, be it the pace of its rebuild or the offensive scheme or even personnel, that could be sticky. But Frazier said he plans to continue a dialogue with Harvin and expressed confidence that there will be no holdout. Which would score me another nickel, if nothing else.