It is not about him. It has more to do with the quality of pitching he is facing.
Who we talking about here? Alcantara? And if so, my point on why he will be a better overall offensive player has more to do with his walk total. He walked around 11% at AA. Frankly it was odd because that was by far the highest of his minor league career when you would expect a hitter to struggle more as the leap from A to AA is fairly significant. I'll admit it could be an outlier but if he continues at that pace as a .260-270 hitter he's been the majority of his minor league career he's going to be a .350 OBP type who's a switch hitter and can steal 30 bags. The reason that walk rate is so important is Castro's peak in the majors is around 5% less than what Alcantara did last season which gives Alcantara a 30 point head start in OBP over 600 PAs. And as I've said before OBP is huge as it's a direct correlation to runs. Also, while Castro isn't making big bank, if they end up comparable offensively Castro's going to be making $6, $7, $9, and $10 mil from 2015-2019 when Alcantara would be in pre-arbitration 3 years and arbitration 1 the 4th. That's $32 mil over 4 years that they could be using else where.
I just see 0 downsides in moving Castro to 2B if Baez can field the position of SS. Last year Baez had what something like 40 errors at SS? Hypothetically let's say he improves and gets that down to 30 this year. What's the downside to playing him at SS even if he's still a little raw? Castro's first season at the MLB level he had 27 in 123 games and had 29 the second season. The 2015 cubs are probably more a team you hope to win 80 games rather than a legit playoff team. So, he can grow into the position at the MLB level. Don't get me wrong, if he can't play the position then he can't play the position. But if they think over time he has the tools to stay there but is still a little raw so what? Castro's first 2 seasons he was a little raw. Hell you could argue he's still a little raw.
And by moving Castro to 2B you're probably making him a better fielder for the cubs as it's less challenging. At that point you make Alcantara take the job from him. I'm not saying you just give Alcantara 2B without proving himself. However, if Baez is at 2B he never is going to get the chance to prove himself because the cubs are going to want to give Baez as many AB's as possible to evaluate him and playing Alcantara at SS in a battle with Castro is probably not ideal since they moved him off the position in the first place. But even if they did that, if Alcantara turns out to be the better hitter you're then flipping Baez and Alcantara around because 2B is the better position for Alcantara.
To me it just seems so much more simple to move Castro once rather than screwing around with both Baez and Alcantara in order to evaluate them. We don't even know if Alcantara can play CF. As far as I can tell he's never once played any games in the OF in the minors. It took Soriano 4-5 years in LF before he wasn't a liability. So again, why make this so difficult? Baez has spent all, as far as I can tell, of his minor league career at SS. Alcantara spent the majority of his early years at SS and they moved him to 2B both to accommodate Baez but also because he was a better defender there. Moving Castro to 2B probably makes him a better defender too. If Alcantara is shit in the majors then fine. Castro's a decent 2B. If Alcantara's better, you have Castro who now has experience at 2B and SS which makes him more valuable as a trade piece. You'll also have given yourself a look to see if Baez is improving at SS before you would need to make any call on trading Castro.
Again, where's the downside?
