Pro: Vrabel is a correction of the Pete Carroll attitude
As a human being, I like Pete Carroll's overly positive approach to his job and to life. Who would not want to work for a guy like Carroll? You know he is going to get you to be your best and he will never throw you under the proverbial bus to his bosses. Maybe he should hold you more accountable at times, but at least you can sleep at night.
But in the NFL, sometimes a team needs a guy who isn't afraid to be brutally honest with you and be a lot more in your face. These are grown men playing a game for millions of dollars (a lot of them anyway) and it can be easy to get complacent. Also difficult to imagine is someone, such as Jamal Adams, leaving the team or staying at home after being told he won't be playing in a game. Vrabel might simply choose to release the player if that is the case.
Part of Vrabel's tougher approach might come through in how the two teams' defensive lines played this season. Tennessee was a lost cause to make the playoffs since about Week 11. But Tennessee's defense, even though they were almost talentless in the secondary, never gave up. The rush defense allowed 77 or fewer yards in five of Tennessee's last nine games and two of the games they did allow more yards were against the Houston Texans.
A large part of run defense is simply a defensive guy wanted to beat the offensive guy man-to-man. Seattle didn't seem to have this hunger overall. Under Vrabel, a defensive player doesn't have a choice but beating an opponent in run defense is simply a requirement.