I haven't yet, but I have tied some up similar with partridge hackle and gold rib. I basically was considering them as hairs ears soft hackles. I tied two in gray and two in olive (which look great in olive btw).
yeah I'm pretty sure it does call for it. I prefer the Grey Ghost myself and have caught a lot of trout with that, but lots more with other flies this year.
my big ones this year have been Olive Matukas, Grey Ghost, Royal Coachman, and March Browns. As far as trout go these four flies are all I have used. ( and done well with judging by my freezer).