You'r problem sounds quite similar to mine. I'm the same as you in that I can go for a LONG time without drinking but when I do drink I often go overboard.
I find that often times I start out the night with the best intentions (ie. not to gert absolutlery hammered) but like yourself, when I get to a certain point I just go into total overdrive and will start downing pints probably every 10-15 minutes. Often I would end up having 20+ pints a night. I have found that I can control my drinking when I'm in a controlled atmosphere (ie. in a quiet pub just having a few quiet ones or at a house).
THe big problem for me is when I go to nightclubs or busy bars. I completely forget my intentions of not getting hammered and get totally carried away. I believe it's the sensory deprevation aspect of nightclubs that causes this with me. With the dark lights and loud music it is really difficult for me to realise that i'm getting progressively more and more hammered. I get caught in the moment and figure that hey, if Ive had 12 pints already and i'm having fun i'll get more hammered and have more fun. Soon, I'm gone way overboard.
On average, I drink 1(sometimes 2) times per week. Not a lot for here in ireland. There was a period of about 2 years a while ago that EVERY SINGLE night I went out I could not remember past midnight.
I know what many will say....give up alcohol. I also have no doubt that I suffer from a form of alcoholism. I put my hands up and say I have a problem. HOwever, I am reluctant to give up booze. THe reason is that I really can't see my life without booze. Sad I know but I really cant see myself sitting in on a friday or saturday night while everyone else is out having fun. I have tried it and I always end up feeling miserable. I know, I know, I should be able to live without booze but in Ireland SO MUCH (almost all) of the social scene for people my age revolves around pubs/bars/alcohol that giving it up would involve becoming a social recluse. I'm not sure but I figure england is somewhat similar.
It's for this reason that I try to control it. I have tried willpower. HOwever, Willpower is not enough. Usually with willpower, I will control it for a little while but willpower inevitably weakens (i can only hold out for sol long) and I fall back into the same old habits. Also, while you may have the will when sober, when your drinkin it's a different story.
So buddy, I try to control it in a different way. I totally balieve that the only way to control it is to change my habits. Everyoner has their own way of doing this but the way I do it is this:
Usually on a night out I'll start out by going to a buddy's house for some beers at aroun 7 or 8 O'clock and then about 11 or 12 head out to a pub/nightclub. Everything is fine in the house and I can moderate myself reasonably and dont feel the need to chug pints. However, the problem begins when I get into the pub. SO, what I do now is, I don't go to my buddys house anymore. I'll go to the bar sober at around 11 or 12 and meet them in there. I find that this helps me control my drinking since I am not already drunk walking into the pub. Also, since pubs here close at around 3AM, it limits the amount of time I can drink. I find that at about 2 or 2.30 I am beginning to wane and down pints but by this time, I only have a half hour of drinking left so I dont end up nearly as hammered as I would otherwise.
ANyways bro, what I'm trying to say is that you have 2 choices:
a) Give up booze altogether (great if you can do it)
b) examine you drinking habits and soberly change them (in the sense that I did above) because willpower alone, will not work. You gotta force a lifestyle change. YOu muyst change your habits. I cant suggest a way. It's somethin you gotta figure out for yourself bro.
Every once in a while I'll fall off the wagon but it has made a big difference in my social life. The worst thing is being known as the always-drunk guy on a night out. I'm only 24 but I wasted many years of good nights out/weekends/times I should have enjoyed myself through my weakness for alcohol and that is something I thoroughly regret.