User blog comment:ZPPHR/Zane/@comment-4881935-20121109025854/@comment-5638912-20121109035950

Yet again, that's because his a Battle Mage. As any other melee champion, Zane also needs the survivability to go in and fight against the other team. Even if he's a caster or the initiator.

I may be tweaking the passive's cooldown a bit. :P

The W's heal doesn't scale from the damage dealt, so it's not like life steal or so.

The E's movement speed indeed keeps him away from the enemy, but also helps him get in range of them.

The R only gives the passive armor and magic resist when in that stance. It's like or, even  also gives defensive bonuses. And I know all of these examples are melee, but Zane's bonuses are smaller than any of those.