What defines a Spey fly? Two distinct features – the low brown mallard wing and the long, flowing hackles, often from a heron. So can you justify adding the “Spey” in from of a fly, which you modify using a long, flowing hackle rather than a more traditional cock- or hen hackle found on most traditional wet flies? And what if the long hackle isn’t even a heron hackle? I’ll steer clear of that discussion for now.