This deal happened because Columbus has an internal cap and likely does not want to pay a guy (Horton) who isn't going to play. At the very least, Clarkson will be playing, so they can manage that. Columbus could put Horty on LTIR, but they'd still have to pay him the actual money with no production in return, and they can't afford to do that. Toronto, on the other hand, has money out their ears, and was willing to pay Horty because they can, and can take advantage of just putting on on LTIR and recouping his cap hit. At the same time, they can't do that with Clarkson, and that albatross contract was preventing them from what they wanted to do.