It's a good question.
Alcohol is processed by your liver, before carbohydrates are.
So you process about one glass of wine an hour, so after the two glasses, simplistically two hours, you start to process the carbs. So, depending on your metabolism, all you may be doing is putting off the inevitable.
You do stop the liver releasing glucose as well though, until the alcohol is processed. So you should see a dip.
Not a bad thing, but maybe not a free pass.
I've also found my overall bs rises slightly if I drink intermittently, and falls generally if I give it up for a longer period.
The New Scientist ran an article
http://www.newscientist.com/article...dry-january-really-worth-it.html#.UvIBUK1FDMw