Late to the party, but I think this is a sneaky good trade by Dean.
Lot of people overlooking the peripherals on this move, and it perfectly fits the MO a lot of folks have been talking about - win now.
We lost 0 - that's a zero - roster players, and all that went the other way is a prospect that was never going to play on the Kings anyways and a 3rd rounder. Neither of those things help us win this year.
We gained the long-rumored Matt Greene replacement, and not only is he relatively young with upside, but there's a crazy amount of flexibility contract-wise since he's UFA after this season. LeCavalier could either be boom or bust, but worst case scenario he's an additional body and (hopefully) good locker room presence, especially for guys like Shore/AA/Mersch.
Only real downside here is cap space was eaten, but hopefully you were all aware that Dean almost certainly wouldn't have been able to make a splashy deadline move without sending a roster player back the other way to free up more cap anyways - and people forget that having cap space doesn't actually matter unless you can turn that money into tangible assets.
I'll say it again, sneaky sneaky good.