OK I'm going to get badly flamed for this, but:
Vastly overrated IMO. The guy always lined up 40 yards behind the line of scrimmage - maybe that was just part of the scheme, but I think it was partially due to his limitations. The other Raider game I remember was the 1993 freezing playoff game when Tim Brown took a ~60 yard pass and just left Kelso out of his jock (Paul McGuire said "Kelso had no chance to make the play" even though he was RIGHT THERE). Fortunately Kelly hooked up with Billy Brooks for a 2nd time to win the game.
Anyway, sorry to be an ass - I'm sure he's a great guy.