i did this (or something similar) last night, on your previous recommendations. 1/2 lb brisket. 1/2 lb sirlion. 1 lb chuck. in the food processor. i was pleased with both the texture and the flavor. the cooking method, however, left a lot to be desired...and that's why i'm on this thread. i think for sure that a thinner patty is the way to go, rather than a fat one at least. although a fat burger is romantic, i've had horrible results. like stone, i've had (nicely) charred outsides, but raw and cold insides. cast iron grill pan for sure, however.