First of all, assuming that Roberts is even available, he would probably cost at least Marshall, Gaudin/Wuertz, and Vitters. There are too many teams that want him to think that he will come on the cheap. Is the increase in SBs for one season at the top of the order worth that?

Second, a LHB at the top of the order isn’t nearly as important as a LHB in the middle of the order. How many managers burn their LOOGY’s for leadoff men? They burn them (often unsuccessfully) on the Chase Utleys of the world. As long as a leadoff man gets on, it doesn’t matter which side of the plate he does it from.

Third, their OBPs for the last two years are almost identical. (.371, .376 for DeRo, .377, .378 for Roberts). Roberts has 90 SB/17 CS over those two years, but DeRo has 45 more RBIs in 253 fewer PAs. According to B-R, Roberts was worth 1.7 BtWins last season, DeRo was worth 1.5. Roberts is two years younger, but he is more reliant on speed, the first tool to diminish. Roberts is better defensively at 2B, though it isn’t really fair to judge DeRo strictly as a 2B when he is expected to constantly change positions. They are both FAs after 2009. Overall, they are about equal in production, just from different parts of the order. (Oddly, Roberts scored only four more runs than DeRo last year despite batting leadoff and having 111 more PAs.)

Fourth, moving DeRo to RF negates the ability to get a run-producing LHB for RF, and Lou doesn’t seem interested in moving DeRo to SS. I would also wonder whether the Cubs could afford both Roberts ($8M) and DeRo ($5.5M) in the MI; budget is the reason they are kicking the tires on Mark Teahan.

The $64,000 question is: how much is it worth in prospects to essentially move your 2B production from the middle of the order to the leadoff spot? As Colin is fond of pointing out, it is much cheaper to go from mediocre to good than to go from good to great; this is basically a lateral move.

The Cubs would probably trade DeRo if they did get Roberts for the following reasons:
1. They can’t afford both.
2. They need to get some value (in prospects) for DeRo since they would be giving up so many to get Roberts.
3. They know that DeRo hates playing OF and would be unhappy playing there regularly.
4. They need the spot for a LHB, and they can’t really trade anyone else (e.g., Lee) to make room elsewhere on the diamond.

Roberts would also spell the end of LBR as we know him since he was dependent on DeRo’s versatility for his playing time. Lou wouldn’t dream of asking Roberts to do the same thing.

Back to the original question: is the trade-off worth it?

(Personally, I would rather see DeRo traded than sentenced to a year in RF. He doesn’t deserve to be screwed like that in a contract year after the season he had in 2008.)

and haven’t really followed the Rangers since DeRosa played there, so I hazard to say right now.

as a practice…well, suck.

You get done what you want with a trade partner, and move on down the needs list. You start adding front-office people, and 4-8 players going back and forth across the country, and most deals quickly fall apart.