I have cooked a bunch of Waygu and even more CAB packers.
I find that the differences are small, with maybe one exception.
The Waygu seems to have a short window for "doneness" compared to domestic brisket. I try to stay of top of it at the end, just as I do with domestic--just a bit closer.
BTW, my first ever Waygu cook was at a comp with a CAB for backup.
First place brisket in a field of great brisket cooks.
I just did it as I always cook brisket and kept a close eye on it at the end.
Otherwize, I think if you start anticpating big changes and make big changes in your cook schedule, you will just wind up scewing it up or being dissapointed.
I would prep and cook it just like always and then "fine tune" later if need be.
Just my thoughts.
"Flirtin' with Disaster" BBQ Team (RETIRED)
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Former owner of a WSM, a Smokey Joe, a Charbroil Commercial gasser (junk), the legendary "StudeDera" and Sherman.
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