2 things I feel pretty strong about with the wooly
1. Make sure the tail is not too long, if your getting hard hits without hooking up this is almost always the problem.
2. Heavy weighted buggers are nice for getting down, and when the fly is supposed to represent a leech or very small minnow fine, but you should always have ones that have only wrapped lead, when that fly is supposed to represent a dragon fly or any other nymph a slower action in the water with less speed to its sink will out fish a weighted fly, if your fishing sub surface on a lake you should be fishing a sinkline or tip, weight on flies in slow water retard their natural looking action, and action is everything.. also, sink isn't that important since a bugger works best often in 2 or 3 feet of water around weed beds or structure, so a lot of the times it is taken as a mistake for a crawling nymph.. I usally cast to shore, often hooking the bank on my cast from my boat or tube... this is where I catch most of my bigger fish. Balancing a bugger to sink level and correctly is a very important part of tying them, then fished with the belly of a sink line dropping them they present propperly, when you put a chunk of shot on with a dry line you have ruined the natural drop of the bug, and less fish will hit it... and don't turn your back on the violent ripping retrieve, Ive hooked hundreds of fish as I quickly stripped to cast again- Good luck ( all of this info is intended for trout in lakes or ponds... steelhead changes many of these dynamics )