Hm. My instinct is to say that you should only be able to transfer icon slots as a whole -- like, you could take all the icon slots from x and move them to y, but you couldn't take half the slots from x and put them on y and put the other half on q. Otherwise it would be way too hard to explain to people, and really hard to code for, and people would be moving icon slots around really frequently (and we'd possibly lose money on it).

But I could possibly be talked out of this if mark feels differently.