About tri lanes, in dota its generally two hide in forest and the one in the lane is usually a person with a ranged stun (Vengeful Spirit, Chaos Knight, Rogue Knight) and then he stuns and two pop out of the forest and deal a lot of damage in a short time (Slardar (Warstomp)+Jugger (Blade Fury, like 500dmg on lv1) work great). You get FB (+200g) and then you go back to the general 2 1 2 lane setup