MMA guys should fall in love with Dogfight/underhook
Stumbled on this piece of brilliance by BJJ Scout.
https://youtu.be/BBwnoxFv7co?t=2m50s
Start at 2:50 if the video doesn't do it automatically.
Now, technically, the underhook alone isn't dogfight, but dogfight principles definitely apply. Same for the Lucas Leites style of half/quarter guard. It all starts with the underhook and you can take it from there.
I hope I'm not going against the Bravo philosophy of MMA guards, but from my observation, every second of being on bottom is a second you're losing in the eyes of the judges. So I feel like any guard that helps you sweep or get back to your feet is the ideal guard for the sport rules of MMA.
If nothing else, at least appreciate the brilliance of Maia's BJJ for MMA style.