Mark Arcobello played for four teams last season and any time you have the chance to snap up a guy like him on July 1st you have to take it. He's a hockey player I guess, the problem here is opportunity cost. At this point you're committed to Arcobello and have reduced your chance to troll through remaining free agents for deals a month from now.
It's only a one year deal at $1.1M so realistically you're only out half of the Kessel salary retention if you find something better and stuff him in the NHL, but this isn't a deal to get excited about.