Tahm Kench W Bug or Intentional?

This was just brought up in a post involved in my other Tahm post but it is definitely something I've witnessed myself.

Tahm's W priotizes allies over 3 stacked enemies if they move super close to each other or if an animation (yi's q for instance) puts an ally on top of the stacked enemy.

Also, without "target champions only" to ready key, his W can easily hit a minion instead of a 3 Stack enemy that the enemy champ moves over