Barq isn't controlled by the player, but he often attacks your enemies when you might not be. Barq can be hurt and taken out of the fight, but not for long.
You can also jump on Barq but I found this jumping not to be very helpful in my experience. Barq is way more helpful as a shield. When a grapple is blocked by Barq, it's quite easy to counter your opponent with a move of your own.
But overall I liked him a good bit. Not in the top five maybe, but close to it.