No words of advice... but I wanted to tell you I sympathize. DS12 picks at his nails, not bite, but picks... clear down to the quick and then some. So, the whole Sally Hansen thing didnt help at all. Nothing to taste when you're picking. I tried jalepeno juice once, and he cried... then I pulled up jalepeno juice online and found out it can burn the skin. I followed the advice found online to stop the burning, and I apoligized to him. I would read up in it before trying this... after reading about this, I personally would advice against it. He picks for no apparent reason... his hands get bored and he picks. He can be watching a movie, in class listening, reading a book, sitting in the car... it doesnt matter, if his hands are busy he will pick.
Sorry, I forgot to add... I tried putting a rubix cube, stress ball, ect in his hands in the car and when we watch a movie but unfortunately these only helped short term.