Different locations and different dive sites require a variety of techniques. Since I hunt in Jupiter, and if we are on a reef, it is always "common practice" to hunt alone. The 2 main benefits are:
1. It's a single set of bubbles or sounds that one person can control when stalking and not spooking the target. 2 sets of sounds will almost always spook prey.
2. You can cover more distance and area by splitting up, thereby increasing your odds of finding your target. If you always follow behind your buddy, he will always get the best 1st shot.
On the flip-side, if I'm hunting in 120ft and know that the fish is going to rock up inside of a small cave that has a back door exit hole, then a buddy team is more advantageous. Like wise a well known wreck where a fish may always hang out at the prop and you need 2 divers to descend on each side to get the shot.
The merits of solo diving and safety backup systems are well discussed elsewhere on ScubaBoard.
I didn't catch these bugs last saturday by following my buddy, since you can see, he also is very good at not letting any get away.