The tendency is to strip the fly fast trying to duplicate trolling speed. Where this will take fish occasionally, a far better approach is to fish the fly as a bait fish which has been crippled. Even the laziest coho can not resist this easy meal. Should you fish down through the marker with out any action, change over to your trolling fly and make a pass. If you still have no action, move on.
Many anglers think that fishing flies in the surface is a early morning or evening show.
Another tactic I sometimes incorporate instead of fishing the debris side of the rip, is to troll a hot spot flasher about five feet below the surface just behind the bubble train. The flies are trolled on the surface up above, and slightly in back of the flasher. I have stood at the back of the boat, using polarized glasses, and watched schools of coho salmon swarm to the surface around the flasher. This technique has kept the fishing hot through the middle of a sunny day. I remember an afternoon that became so windy, that we took refuge in a sheltered bay, on the lee of the storm.