We still have to encourage J to go to the toilet, DP has told him the toilet has to be fed everyday lol, "the toilets hungry!" we use the milky way stars too! and he gets a sticker on his chart, but if we didnt say anything he would still not go on his own.
I think because J was so bad, it may have damaged the nerves and stretched the bowel so now he doesnt recognise the " I need to poo" signals.
Just make sure to keep on top of it, it seemed like as soon as we thought all was good and stopped the parachoc, he would just revert bac, or something would happen and it would all have to start again.
His diet if fantastic, hardly ever gets junk (apart from the "poo stars" lol) eats so many varieties of fruit and vegetables.
I give J a yakult thing every day now too, seems to help.
Good luck with it, I think with the parachoc it can be safely used for a while but under docs supervision and like all laxatives can lead to dependence if used too much.