I think you shouldn't be thinking about going parallel. Just make a turn that your body is capable of.
I was playing the other day, when after a few holes one of my playing partners reminded me I was swinging parallel, on my tee shots. I was doing this subconsciously. When I got to a tee box, where I could see my shadow, I looked at my swing to see if I was going parallel. Needless to say, I put the thought in my mind and looked at my shadow instead of the ball. That was my worst tee shot, a grounder.