The Ponson move is a great move by the Yankees. The Yankees are paying nothing to get him, so here's essentially what's happening. The Yankees are getting some undefinable quantity in exchange for nothing. In addition, the Yankees staff includes HOF'ers like T.J. Beam and Matt Smith right now. If Ponson sucks, he does nothing worse than Beam or Smith could've done. However, if he gets his act together (which he very well could), he becomes a true asset to this team and could be a solid #3 for the staff.
Oh, and I don't agree with those who call Cashman "clueless". He's had pretty good reasons for most of the moves he's made over the past 5 years. A lot of them simply haven't worked out like they "should have".