Hart is probably a decent poker player.
Have heard both Bowden and Jim Duquette say on XM that he was by far the one guy they didn't feel comfortable going to bed and agreeing that they'd finalize everything and send it in to the league office "in the morning". They both have said that if you've got a deal with him you'd better get it done NOW because he'll move on and take what he perceives as a better one in a heartbeat. They've mentioned he's talking to EVERYBODY all the time about EVERYONE, so it's easy for him to find a better deal (in his eyes) if you hesitate.