Putting Hitch’s theory to the test…
Personally I think that if as a writer you have to suffer from a disease, liquor may be quicker (and Hitchens was very, very quick), but bipolar is better. 
And the combination of the two, until one or other becomes overwhelming, may be (for good writing) better still. As examples over the last 100 years suggest.
Perhaps the question needs to be clarified. After a drink or two, I may write more quickly and colorfully, yet not necessarily better, just as I may be more voluble without being more articulate.
An experiment which one of my sons and I developed, and repeat with consistent results:
1. Find a simple word game and a simple logic game.
2. Complete one of each.
3. Have a glass of wine and socialize for a few minutes.
4. Repeat #2.
5. Word game score goes up and logic game score goes down.
As with writing, there is a point of diminishing returns, frequently reached too soon and often driven past unnoticed.
ps
Alcoholism does seem to afflict American writers in particular. Five of the seven American Nobel Literature laureates suffered from alcoholism and Sinclair Lewis famously asked ‘‘Can you name five American writers since Poe who did not die of alcoholism?’’
I’ll try. First, here’s a list of writers who suffered from alcoholism: Ernest Hemingway, F. Scott Fitzgerald, Charles Bukowski, William Faulkner, Jack Kerouac, Truman Capote, Edgar Allen Poe, Dorothy Parker, Tennessee Williams, O. Henry, John Cheever, Raymond Chandler, Hunter Thompson, Sinclair Lewis, Eugene O’Neill, John Steinbeck…
And those who didn’t: Nathaniel Hawthorne, Mark Twain, Mary McCarthy, Upton Sinclair, Emily Dickinson, Henry Thoreau, Zane Gray, Ralph Waldo Emerson, Saul Bellow, Robert Frost, Edith Wharton, Willa Cather, James Michener, Lillian Hellman, Tom Wolfe and Flannery O’Connor.
The moral of which is - you don’t have to be an alcoholic to be a great writer. But statistically it improves your chances of winning a Nobel Prize!
You can add Stephen King to the list of alcoholics. His take on it is that saying you drink because it helps your writing is just another excuse, no better than any of the other excuses alcoholics use.
Katherine
I resist alcohols. If I were stuck for inspiration and that I need new subjects for paintings, I simply switch on binaural music and listen to it at low volume. That really helps to spur on my imagination, jog my thoughts and get ideas flowing out onto paper.
Folks, try binaural music instead of alcohols or drugs. 
Drinking doesn’t help my writing. Though it can help quite a bit when i am reading something like Whitman or Thomas. Everything in moderation. Being master of yourself can lead to more profound moments of clarity than if you’re a slave to an addiction. I say drink up when you’re out and with friends. Ask them questions about their families and such after they’ve had a few. Talk less, listen more. Gain some perspective. Thats seems to be the best way to tie alcohol and writing together in my experience.
Kurt Vonnegut’s answer to this question was “No.”
My experience is that alcohol doesn’t help me write – but it does help me socialize, during which I tend to free-associate and come up with fresh ideas. I’m a storyteller; having an audience makes it easier for me to come up with interesting stuff. The writing then happens the day after, while stone-cold sober.
(Writing while drunk tends to result in lots more re-writing when sober. So best to leave the beer until after the working day is over.)
I tried drinking while writing and it just didn’t work for me. My typing suffered and the ideas came out less and less to the point where I ended up saying ‘screw it’ and just passing out. Coffee and a cigarette in the ashtray are my staples.
Seemes to me tHat dirnking is the most most most PWOREFUL tool thta any wirter can ooh look there’s Ed Balls I CAN SEE YUOR EYES MITSER BALLS I KNOW YOUR’E BEHDN THE MOLNITOR can can, um, to which can POSIBSLY HAVE ACCCESS TO. I not olny THIMK better but I also WIRTE better wenh Iv’e had a few tublers of KRAKEN RUM inside me but aslo another one on teh deks in frNT OF ME As I type, it maske the IDEAS flow and resleases my inner CIHLD and inagimative self why oh why do we have to GORW UP? when I was a CHLID i was happy all day and BLIETH and untrma untarm untramlllel untr untr not in the chains of the WLORDLY CONCERNS wich which Im sorry I dn’ont usua;;y cry into the kyhboard it’s juts so very very very very sad I blaem my mother have another one no rlealy just a little one anothre little drink wont’ do us any harm as Jerrfey Bendard use to say and he was a GENUIOS is’t so tebbrily sad…
So, yes, it djh dh deo dsoe BOLLOCKX does and anyoen who say othrwise I’ll puncj him in the threot OKAY? I am SEIROUS. THe sodding THROTE.
I apologise for the above post. It’s this Bluetooth keyboard. Honestly. I was just very tired. And anxious. I’m fine now. Starting tomorrow everything will be different.
Encore! Mr. M….Encore! 
Brilliant.
I also have a new understanding of the comments following online newspaper articles. 
This topic is sort of old. But I’m new, and in reading it realized that I’ve thought about this question quite a bit.
I used to be very curious about how a writer could be a serious drinker and still write. Actors, ditto, by the way.
And I think the answer is . . . they don’t necessarily get “drunk as a skunk” and then write. I think they drink continually, while they are writing, and the brain uses the alcohol so that it can keep working.
Haven’t I read, somewhere, that our brain uses [ fill in percentage ] some large percentage of the glucose produced by our body in its normal functioning?
I think they’re using the alcohol as fuel. And if they don’t overdo it all the time, as in binge drinking or drunk-as-a-skunk, it looks like it works.
FWIW, though – not recommending this. Just suspect that’s the reason it’s so common.
Nice idea. But sadly, no. It’s not that.
While you are probably right that many alcoholic writers drink continuously while they are writing (I’ve never watched an alcoholic writer in action to verify this), the reason is not they use it as a fuel. Yes, there are sugars in alcohol, and yes our bodies can use some of them (I’m not a nutritionist), but it’s an inefficient way of powering the brain. Basically, excessive use of a poison to try make the body work is never a good idea.
The reason why some writers use lots of alcohol is actually very simple: alcoholism. The mechanisms can be explained by two of the key concepts of addiction: tolerance and withdrawal. Add them to the reasons why they started drinking in the first place, and you have a pretty toxic (literally!) combination.
So it’s not that alcohol helps writers write, just that it helps alcoholics write. But that’s not saying much as it helps those with an alcohol dependence do pretty much everything other than reduce their alcohol consumption.
You guys may want to google ‘functioning alcoholics’ or ‘functioning alcoholism’. It’s not just writing or acting, all sorts of professions/jobs have it. The current dogma is that functioning alcoholics are constantly at risk of trespassing a threshold and becoming no longer functioning. There is no hard data on this though. Indeed, even the concept of functioning alcoholism is not based on hard data. Alcoholism is by definition a disorder, if someone is functioning, how can she/he be alcoholic?
Cheers!
See tolerance and withdrawal.