Just had to share this with you. I’m sure some of you may have already realized this, and/or maybe read the same book (don’t remember the name at the moment - still at the store).
It made a mention of the self talk that we put ourselves through when we sketch. We think (using some of my own here 
), “there is no way that the arm can be that long” or “the head is too large” etc, etc. If I recall correctly the book suggested that instead of having that type of conversation with one self, we should be thinking something like “this angle should be like this” or “the distance between this eye and the other eye is this much” etc. I mentioned that to my wife and I heard laughter of agreement.