Fight against Abraham Okine in 2005, and he looks pretty good. Not exactly the fastest HW I've ever seen, but his power is readily apparent. I don't think Okine is a total can either...he's 14-0-0.
Yeah, Briggs had a lot of natural ability, he even had pretty good slickness and head movement before he bloated up to 260-280, and even than he had it good for his size, decent hand speed, and great power.... Asthma hurt him, a lot.