Igor and Bob K,
The answer is no. The original Glasso dressing is just a little bit darker than his Sol Duc, which uses G.P crest for a short tail, TEal face hackle, and a G.P. crest as a wing topping. If you use teal instead of black for the face hackle, it in effect is nothing more than a Sol Duc fly without the G.P crest feather, and I'd rather tie and fish the Glasso flies as he designed them because of the progression from light to dark that they have.