The cookbook I have says to cook haggis with the windpipe hanging over the edge of the pot so the "black impurities" inside the lungs can drip outside the cooking pot.
Ny cookbook also says there is a clear dichotomy between those who cook haggis and those who eat it. The authors stated they could find no cooks who would eat the resulting dish.
I live in Maine and my cookbooks range the world, So too does my music and, since I found the Mudcat, my friends.
No regionalization here!