First item tabis should not be a legitimate build.

But why? Armor, move speed, and reduces damage from autos. Thats like Thresh first item Moba boots. Or Hecarim first item moba boots (after a smite upgrade).

First item boots has been an accepted legitimate build for about... oh... seven seasons now. Tabis is just the armor boots you take when the enemy is physical damage and Mercury against most Tanks and magic damage.

Otherwise I would've just commented here (follow through from your reply)