Compare Heavy tank Armor to scout defensive system

[GooglyBoogly]

I used to think tank armor worked and/or did something useful.

It would have been great laser defence. Laser does 80 dmg, minus 40 for the tank armor, is half damage from lasers.

But unfortunately, tank armor does nothing versus enemy tanks? Great ability!

not at all: It protects you against minions created by the demon tank, the infernal tank. Summons from the Guard tank and the Ghost tank. And summons from the troop command/adv troop command.
It protects you from tinker tower damage too.