Doctorfish,
A 12 pound blackfish will pop locked 20 or 30 pound mono (or braid) like it was sewing thread, even with the stretch. Anglers fish the maximum pressure that the strength of their line permits. If you totally lock 30 pound test, you will break off large blackfish. What Capt. Neil was saying is that you set your drag to rating of the rod, meaning that if you fish 50 pound braid on a 30 pound blank, you set your drag as if you are using 30 pound test. In answer to your next question regarding a fish pulling you into a wreck beyond your leader and the braid gets snagged, you simply wrap your end of the line around a small piece of metal pipe and break it off. When I fish braid, I always splice in about 10 - 15 feet of mono at the end the braid. This gives you the stealth of mono with a little bit of stretch and still provides the sensitivity and thin diameter of the braid.
Now back to the orginal question, I think that braided line is a big advantage in the deeper spots, but in shallower water where light is strong you should stick with mono.
Gamakatsu