This yellow/brown combo has proven to be the top color selection out of all the colors used. After years of this fly being our top dry fly imitator on countless DH and wild streams including blue lines, we've determined that sizes 12 & 14 are the best and only available options for purchase. Mountain streams to mid-sized streams go with #14. Western waters and large tailwaters where you want to drop a lot of weight, go with #12.
For the tailwater of the Chattahoochee, South Holston, Watauga I'm almost always fishing #14.
Fished year around and have dropped up to size 8 leech or bugger off this while using as site indicator.
Because the primary material used on this fly is CDC, to get the best use you must treat the fly before, during and especially after you land a beautiful trout. From experience we've found that a very small application of Loon Lochsa to start the day rubbed into the CDC fibers, and then a coating of Frog's Fanny works really well. After the first treatment of Lochsa, you should be good with just repeated dressings of Frog's Fanny throughout the day. Failure to keep the fly coated after landing a trout or once you see it not riding high in the water, will significantly decrease its potency.