Severson is not a top pairing defenseman. Didn't they have to shelter him in NJ this season?
He wasn't sheltered per se, he was on the 3rd pairing because Dougie is one of the best offensive D-men in the league, Marino exploded for us this season, and he (Damon) provided stability and leadership on the backend due to rookies and garbage Brendan Smith being on the left side.
He's also a very good pk'er and a competent pp2 qb.
This isn't a bad deal for Columbus- even if years 7/8 will be rough - since there was no chance he was going to get less from a better team on the open market.
Most Devils fans would've been very happy to have him back for 2 years but he never would've taken that deal and with Nemec coming up as soon as next season there was no reason to sign him for longer.
He's going to do exceptionally dumb shit occasionally, but overall CB made a good decision and acquired a fine puck moving 2nd pairing RHD who can slot in on the first and not look out of place with a decent partner.