I converted to scarf over brace about 5 or 6 years ago and have been very happy with the results. I’m not a 'true student' of historical frames, but the location of scarfs is a feature I look for. I agree it is not the norm to find the scarf located over the brace, but I have seen them there. I’ve also seen examples of the scarf over the post with the scarf showing signs of separating due to high bending loads.

Thanks,
pete