The hardest (or easiest part) is getting that foot control. If you have the foot, you can instantly hit the rolling toe hold.
Depending on your opponent, he'll either give you the foot or he won't.. if he doesn't, fighting for it will just get you into deeper water.
Tavares is awesome, and this move theoretically resolves a problem I have countering the breimbolo. I would grab the foot like a toehold, dive for a missed toehold, and then try to kick them over using my leg as a hook. This move always resulted into a scramble. I like Tavares' angle better, since it seems to get the hook in deeper, to set up the back take.