If he's the guy we saw -- grand-stand down the left-field line, just past 3B -- he's great. Just the kind of loud-voiced cheering that a team needs. The guy I saw was leading "Let's go Nats", and "Lar-ry Way-ayne" at Chipper Jones.
The stadium has a fan-base when it has people like him, and no longer needs the "Nat Pack" to start noise.