I remember the husband of a cousin of mine in carrier jet pilot flight training got really upset and tense over it. He started to drop out. His commander thought he had the makings of a good pilot though, except for his nerves, and strongly suggested that he "go out and loosen up, just get drunk" with some of the guys that were already doing it. He didn't mean being drunk during flying.
The flier decided not to do either and changed from pilot training to navigator training. That was less stressful for him. He made a career there.
A lot of guys did go get drunk to "loosen up."
If you loosen up so to speak you will think of different things from what you think not drinking. Not all good or course.
Otherwise I think it is just excuse given to justify what you are doing because you have problems. Of course after you drink enough, the drink is the problem, so it works full circle. If you really need that drink, probably your writing is going to be adversely affected. What you need to do is to change your habits until you don't need that drink and then you can be really productive.. Smoking is the same way.
By the way, I have known a lot of very proficient drunks. Some were talented and very skilled at different things. The alcohol only hurt that talent and skill. Never enhanced. it.