That is essentially what I was talking about as well..
I read in some old book on tuning an engine years ago, that having someone rev the engine (like hold it a 2000 rpm or 2500 rpm) while carefully pouring a thin stream of water down the carb venturis, would break up the carbon in the combustion chamber.. The key is to regulate the thin stream of water listening to the engine so as not to feed too much water that the engine stalls. I have used this method before as well.. Especially on a stock or low compression engine there will be plenty of room in the combustion chamber for a little fluid with out hydro-lock occurring..