Pedro circa 1997-1999 was freaking ridiculous. If they had 1999 Pedro, I could see your argument, but Pedro 2005 isn't the main difference. The main difference is the entire pitching staff- Pedro 2005 would've helped, but when you stack your rotation w/ #3 guys, your closer is gone, and your middle relief is dreadful, you can't expect to win.
Granted, last night's performace by Wells was good enough to win (if Graffanino makes that play, the Sox get out of the inning 4-1 or 4-2 at the worst). But a best-case scenario Game 5 w/ either Clement or Arroyo does not look promising, especially w/ the Sox all of a sudden not being able to figure out Contreras.