Imploding Dice: When the result on a die is a 1, then it implodes. This means that you get to sum the two dice, and then reroll the one that had the 1 on it, and subtract that from your total. You would continue to do this as long as you continued to roll ones on the imploding die. Once a die has imploded, it cannot explode during the reroll process
I can't see that making any appreciable difference to a task roll. You'd have to roll 1s a goodly few times, and at a 10% chance, that's never going to happen as frequently as needs be. I'm going with a re-roll on the 1s as usual, but then a re-roll only on natural 10s. I've used it in my own homebrew games and it works fine.