Rasheed Lewis is like THE expiring deal. You could use his contract so many ways, and they chose to pick up below average starters with bad contracts? This just doesn't add up to me.
1) Okafor is not a below average starter. He's a significantly above average defender, capable of defending 2 positions, and a great teammate. You could argue he's an average starter I guess, but I'd say there are more centers who started 50 games last year he is better than, then there are centers who started 50 games last year he is worse than.
2) WHo knows what deals were even out there for Lewis? The teams with big names that they're willing to trade (example, Lakers and Gasol, Magic and Howard, etc), are looking for more in return than cap space they can't capitalize on for their stars. I could see a guy like Boozer or Stoudemire available maybe as well, but why gamble with their long contracts?