Completely unnecessary, in fact quite likely to prove a bad idea.
Behind solid rotation depth, better to have solid young guys with upside to send to Maine to develop if necessary and play bench minutes in stretches where starters rest or are injured.
I'd rather build something to root for on the side than have unnecessary and controvertial vets with big egos and marginal talents trying to hang on to contenders-only to validate their oversized sense of their own value and importance.
Give me Joseph and Christmas over Barnes and his like.
EDIT: Both players look like the Kevin Gamble-types, guys that develop a bit to have very good overall games and become solid rotation guys for short money off the bench and fit in perfectly. That is a thing to give up to sign anyone, and Barnes on the third string isn't a greater asset than Joseph and Christmas.