I'm not quite sure what the purpose is here,; drink all you can , get pissed, enjoy what you doing and be able to talk about it tomorrow.
Having anchored a few boat race teams, it take about 8 seconds to down two beers, but I guess that's not the point.
Now that I'm older and wiser, it's about a full pint an hour until it time to leave, if somebody is driving.
I can take me a full hour to truly enjoy a fine Malt, no ice of course. if the plan is to get my blah blahed, then even longer.