Bruce,

When the Purple Haze craze started a few years ago (first tied by Andy Carlson from Hamilton, MT), I definitely wasn't one of the first to jump on the bandwagon. Purple? really?
Eventually tied up a few and then one day while fishing the Clark Fork (just up I-93 from Hamilton), with nothing showing on top, I tied one on and was in business for the rest of the day. I've had good luck with them and various other purple-bodied flies ever since.
Don't know if it's related to spectral wavelength, lack of familiarity, whatever. What I do know is there's a distinct lack of purple insects on the waters I fish and the trout don't seem to mind one bit.

Regards,
Scott