Those who run long leaders, fish deep, and sweep the drift will floss fish - INSTEAD of getting them to bite.
Cohokid, it really depends on how you fish. One thing I can gaurantee you is that I have seen coho chase bait and hardware...I know they bite. Maybe your friend need to shorten up a bit?
Every year bug pumper, winter steel and I all get a handful of coho caught on the retrieve! If you hit the right bump of fishwith a tide or rising water, it happens.
BP and I had a great cap trip maybe 8+ weeks ago...15 or so fish in 40 minutes. This was in the cable pool so we could see the fish come up from behind and grab the roe on the retrieve. In fact we intentionally revieved slow thru the tail out just to try and raise a fish! That tactic works well with ghost shrimp too.
Bottom line is coho will attack a properly presented lure or bait.