Streamers - Mending Downstream?

I am still in the learning process on this stream / trout fishing thing. The Chattahoochee River the only stream I have ever fished for trout. This is a tailwater fishery, typically 100 - 150 ft. wide of varying depths with lots of trees and other structure in the stream. I understand the upper layer of water is frequently traveling faster than deeper water and you ned to mend upstream fishing a nymph so the fly travels at the same speed as natural foods and materials. BUT, if you are fishing a streamer, imitating a swimming animal, fish, etc., which (at least in my old bald head) be traveling a little faster than the stream if moving down stream, Doesn't letting your surface line pull the streamer faster than the deep water current make sense?

I suppose we all develop our very own technique of fishing streamers and that no doubt is what works for us! Obviously conditions are going to play an important part. When fishing water like your description for the Hooch what I do is fish the water in a diagonal up/across stream so the streamer hits the water, sinks a tad, and the floating line will kick up the streamer speed not only as it travels downstream but especially as it arks to the middle when reaching line length. Then the upstream retrieve adds to the possibilities as well. And a real successful streamer for such an application for me has been the Black Nose Dace.

This works best on an undercut bank, but also on drop-offs, overhanging brush, grass beds or anywhere where there's a line of cover.
You cast your streamer up and across to the top and immediately give it a strong down-stream mend.
The purpose of coarse is to get your streamer moving as quick as possible with out yanking it away from the cover line.
Great technique.

I wrote this FAQ on mending years ago but it covers the basics.

http://www.uky.edu/~agrdanny/flyfish/faq/FAQ-6.HTM