There's def. people underrating Gus. I think the fight will be competitive through the first 3. There's alot of things working against him though. Coming off of the Rumble KO, his confidence shaken, the injuries(last cancelling the Glover match earlier in the year), among other things.
For him to win he's going to have to stay determined through grueling clinch work and taking some big shots. DC is giving up size but closes the distance faster than Jones, Rumble, Hamill, etc. DC's boxing is also among the top of the division even though he went full wrestle mode after being rattled last time out.
It's going to take alot of consistent body work with Gus' usual body jab, knees to the body, and teeps to the body(w/o his corner yelling it out...). Cormier's vulnerability to that has been established(not that any fighter is immune). There's a decent chance he wins a competitive decision or even a late T/KO.
Nevertheless I have DC by round 4 RNC. This really could have been a better fight under other circumstances with Gus rebounding first but as it stands I think it's bad timing.