Jon Heyman has a list of the most overpaid and underpaid free agents this offseason. Three Pirates (Kevin Correia, Lyle Overbay and Matt Diaz) make the "overpaid" list. (Jayson Werth tops it.) Scott Olsen is at the bottom of the "underpaid" list, which is fine.
This list inspired me to look closely at the terms of the incentives in Olsen's contract, which I really hadn't before. The Bucs are only giving him $550,000 in base pay ($450,000 plus a $100,000 buyout), and anything beyond that depends on how many games he starts. He'll be pretty cheap if he starts 15 or fewer, but the Pirates will pay $175,000 each for every other start from 16 to 24 and another $175,000 each for every start after that up to 33 games.
$175,000 for an August or September start by Scott Olsen is far too much to pay unless he turns out to be shockingly good, so it looks even more clear, based on the contract, that the Pirates don't really intend to have Olsen start the whole year. Instead, it seems likely that he'll begin the season in the bullpen and only start when someone falls apart or has an injury. They can use him as a starter only as a fill-in and get pretty good value for him that way.