I could not, as usual, get anywhere with photobucket. I believe what you are talking about is referred to as a diminished haunch. The Dutch barns I am working on have diminished haunches on the braces, and wherever a beam meets a post. This is a scribe rule trait. When scibing the brace to the post, you would have a standard dimension that you diminish the haunch. In the barn I'm working on now, it is about one inch. There are scribe marks down the posts that you could line up your gauge at zero at the top of the mortise, and one inch at the bottom. Hard to describe. I will try a sketch of this, but I don't know how to share it when P bucket is not cooperating.

Member, Timber Framers Guild