I used to drink a few when I first starting brewing, that was the point right??
But after I poured a batch into an unsanitized carboy, that quickly stopped. I was amazed how much better my beers starting turning out when I stop drinking while brewing and started paying attention.
I usually don't have my first until the wort is in the carboy. If I am doing a double batch, I will have one with lunch which is right about the time I am done with the first brew. Most of the time I brew by myself but when I brewing with my buddies I will usually have a few, but keep the brew simple.