Reports today have come out that Ramon Santiago has agreed to a 2 year deal worth a total of 4.2 million to return to Detroit for the next two seasons. Many on this site preferred Santiago to Barmes and advocated going after him. To me, they're pretty similar players. Perhaps not in skill-set, but in overall production. I don't think it's any more likely that Barmes will flame out or break out in Pittsburgh as it is Santiago would have. They're the same age and both have their issues.
The Pirates signed Clint on a two year deal for 10.5 million. Had they been more patient, there's a possibility Barmes would've already signed elsewhere.
There's also the possibility that the Pirates would have signed Barmes for a considerably cheaper rate given what Santiago got to return to the Tigers.
And then there's always the possibility that it could have been the Pirates, not the Tigers to sign Santiago had they preferred that. It would have taken an over-payment to go from an ALCS team to a perrenial loser, but certainly not as much as we'd paid Barmes.
Perhaps I'm missing a large component in this whole thing (And please correct me if I am), but I'm just not putting together the facts of why Santiago is worth over 3 million less per season.