I don't think so. The style arms on Black Gamecock are usually distinctively brighter and redder than the petals. Also, its standards are usually a somewhat different shade of purple than the falls.
Very pretty one but I would be afraid to hazard a guess as there are quite a few dark purples out there. Has your friend been growing them for long? That might narrow down the possibilities.
"The chimera is a one time happenstance event where the plant has a senior moment and forgets what it is doing." - Paul Black
