The Cardinals see themselves pretty much in the same boat the Astros were in several years ago. You know, when they had to trade for guys like Miguel Tejada or sign a veteran arm or two. The farm system was weak, the team was not that far off from the days of the World Series appearance, the core was set and you had at least one player making over 100 million dollars in contract. It was prudent to sign veterans or trade for them and try and win that way.
Now the Astros are trying to build a young team and signing a veteran like Berkman would be a step backwards *UNLESS* the veteran takes a job as a backup/mentor. And Berkman was not looking for that sort of job. The Cardinals may get a bump from this signing, even win the NL Central, but the chances are not on their side. The Cardinals fell apart last year because their pitching was bad the second half of the season. Wainwright, Carpenter, et. al. were not that good for some odd reason and the bullpen was mediocre at best. Maybe the Cardinals believe that was an abberation and all they need now is one more push with the veteran team they'll put out there. Good luck to them. One thing about veterans, they can be fragile and if you have no farm system to back up those guys, then you'll hurt your chances if said veterans good downward in performance.
Good luck to Lance and his new team of veterans trying to win just one more title with the veteran team they have. It might work, but the chances are against them if they don't have a good mix of youngsters to place in roles to help win. Colby Rasmus can't be the only one they can count on to help.