Could Dontrelle Willis Be Injured?

As Tigers fans covet the most colorful Easter egg that the team could've left in their basket, with the reported signing of Miguel Cabrera to an eight-year contract, perhaps there should be some concern about the teammate that also came to Detroit in that blockbuster December trade.  

Could there be something wrong with Dontrelle Willis that we don't know (or haven't been told) about?  From Buster Olney's ESPN.com blog yesterday (subscription):

I watched some of the game, but admit I wasn't looking that closely at Willis while flipping back and forth between the Tigers game and NCAA Tournament first-round contests.  So I didn't notice Willis trying to get loose while he was on the mound.  

But in a Detroit News recap of Friday's effort against the Toronto Blue Jays - during which Willis gave up five runs, seven hits, and four walks in 3 1/3 innings - Tom Gage pointed out that Willis is the only Tigers starter who hasn't pitched at least four innings in an appearance this spring.

The D-Train, however, says he's fine and that he feels strong.  And Jim Leyland thinks (or is saying publicly) that Willis' struggles are due to his "funky delivery" (or "variations of funk," which would be a great name for a band) that hasn't found the right mechanical consistency, and thus made it difficult to locate his fastball.  

So do we chalk this up to the classic (trite) Spring Training excuse of "he's just working on something"?  Or is this the sort of thing that compelled Leyland to say the Tigers aren't ready for the regular season to begin?