Walks don't really matter. It's OBP that matters. So while Uggla walks a lot, his OBP is still at around .350 over the last 5 years, and only .329 over the last two. The 4 years before last year (which I'm chalking up as an anomaly due to injuries), McCann posted a .362 OBP (with a .482 slg, which is also higher than Uggla). Even with McCann's power being sapped last year and having just 4 extra base hits in the last two months of the year, he still ended up with a higher slg than Uggla.
To me, it's about who's the third best hitter on this team. I believe Justin Upton is #1, and Heyward is #2 (as much as I love Heyward, I don't trust him nearly enough at this point in his career to call him the best player on a probable playoff team). If McCann is #3, I probably bat him leadoff. If you think it's Freeman, I probably put him at cleanup, and have Heyward leadoff.
It's all moot anyway. Fredi is going to write a traditional lineup (and truthfully, the difference between an optimized lineup and one where you draw names out of a hat is only worth 1 or 2 wins throughout the season at most) because he's more of a traditional guy, as are Wren and Sheurholtz.
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