And why not? There is no law that all big free agent signings are successful, is there? Just because a guy bombed bigtime here, whether through his own fault or not, doesn't mean we didn't take a risk on him. That's revisionist thinking, and it's actually quite sloppy.
Theo operates through trades, acquires veterans for excess rookies, and develops his own players, supplementing from free agency mostly as a Plan C. When he really needs to, he's not afraid to spend, it's just not his first option. This is not a bad thing, especially when you're competing against a team that can really screw with you in free agency. And if you're willing to take on salary to bring a quality player, that should allay the accusations of cheapness anyway.
Besides, among the big free agents we signed are several players who have hit free agency and been re-upped. Schilling and Lowell probably most recently. That counts, as we wouldn't have kept them otherwise.