The corned beef brisket will cook up fine for chili, it is not the same a regular brisket for chili. I would use chuck steak instead of the corned beef brisket. You definitely want to soak it in clean water for at least 24 hours, changing the water every 8 hours or so.
I'm feeling bearish, and I'm packing a Wusthof Grand Brisket slicer from MABA
Whip It Off, Chambers!
"perhaps...but then again...maybe not..."