I've quarter pointed many beams, but they always have another ply spanning the full span of the beam section with the quarter pointed ply supported by one end and at least running past one post. With the entire beam spliced, it would be logical yet unnerving (no supporting plys) to set the splice at quarterpoint, perhaps with the longer canterevered beam section joined so it rides on top of the shorter cantilevered beam. I agree with the concern of reducing the beams depths at the post where all the shear is. With a joint over the post, may as well butt joint it for full bearing with a top spline to tie. Not as sexy a joint though. Any engineers have a general opinion for a rule of thumb?