This issue is still very much present, it was not fixed. Behemoth roll is an instant autoattack cooldown reset. You know the time (half a second or so) between your autoattacks that prevents you from rapidly attacking your target multiple times per second? Well the roll enables just that. You attack, roll, attack, roll, attack until your traversal stamina depletes and you cant enter any more rolls. Using this exploit you pin someone up against the wall so they cant be knocked back and you use the technique i described as fast as you can mash buttons. It will result in multiple autoattacks per second being thrown at your target basically obliterating them. This exploit can easily win you games since when you down an important player like a medic its all downhill from there. It can also be used more discretely, for example just once - attack, roll, attack, that results in two instantaneous autoattacks giving you a nice little boost in damage when you need it at killing a player.
I do not feel that the use of this technique was intended by the developers (though there are some who call it smart use of game mechanics) and i was happy when they announced that they plan to remove it, but alas after the patch i discovered that they only nerfed traversal stamina. That makes behemoths mobility even worse and does nothing to prevent the use of the rollx abuse. In my opinion the lack of in combat mobility is one of the biggest behemoth problems and they worsened it.
The simplest fix would be to just remove the auto attack cooldown reset that entering a roll provides.