I think we may be overcomplicating this. It seems obvious the Jays target guys with good bat to ball skills - and typically ones that have a good approach/eye at the plate. It certainly seems like they believe they can take that player and improve their bat speed and thus power, which can transform their value.
There was an article late last year that showed stark improvements in bat speed by several Blue Jay players and they credited Popkins for helping these players increase their bat speed as the season progressed.
The current version of Bateman does raise all the concerns sliderguy points out. There are all kinds of guys who have success in the minors backed by a passive approach, a good eye and finding holes with groundballs (v. relatively poor defense). It's true that approach rarely plays at the ML level, as pitchers just attack them, with little fear of being burnt due to lack of power (while backed by much better defenders).
I fully expect the Jays know the floor for Bateman is some 85 wRC+ backup OFer/pinch runner. What they hope to do is help him increase bat speed and overall power, to the point pitchers have to respect it, allowing his eye and ability to take a walk to play at the ML level. Fingers crossed it happens.
CFers are SO hard to find, that I certainly don't disagree with this approach. Finding a CFer who's already a complete hitter, with power and good defense is near impossible. Teams don't trade guys like that unless they're the Mets (PCA).