Maybe they think the defense is a concern, so if they think the bat isn't a 1000% sure thing and he ends up moving to 1B then I guess there's a chance he just becomes Kendrys Morales? IDK
Maybe they think his health is a concern, so he just goes full Prince Fielder on us?
I think its a head scratcher for sure - Vladdy's gotta be a low risk at this point