Isn't it simpler to just throw it all in at the beginning? I mean, @park.miles, I used to add chunks slowly too. But letting it burn down early gives a cleaner smoke, idk. Maybe it's just me but the meat doesn't taste as bitter.
At last year's cookoff, everyone was adding wood slowly. I switched to your method this month and the flavor is much better. Used to think more wood meant more smoke, but it's cleaner now.