Toronto, I have to disagree, the flanken cut is traditional to some areas. But, my friends here, all the Korean ones, prefer the butterflied ones, and they say it is traditional to the areas they are from. They also get pissy if you remove the bone by accident.
I'm feeling bearish, and I'm packing a Wusthof Grand Brisket slicer from MABA
"perhaps...but then again...maybe not..."