The reason is that he seems like a super cool guy. And that is ok. Aside from that (which is partly why I'm biased, honestly), if the Yankees version of McCarthy is the true McCarthy then he's a 4-win pitcher if he can stay healthy all year and he's allowed to throw the cutter, which he was able to do this season (he was a 2 win pitcher in 90 innings in NY). Shields is also a 4-win pitcher. Shields is older, more expensive, but more durable, but the Cubs have pitching depth if McCarthy needs some time off, so they could get Shields-like value out of someone who costs substantially less.