Patrick, I've seen your videos and know that your proportions are not common. It's true riders with longer legs typically need more setback. However, I do believe you can benefit from this new style fit from everyone else. The point is open up your hip so that you could do the sphinx position for longer without interfering with your power ouput.

The immediate consequence of a steeper seat angle is that your weight is shifted forwards, so the front centre has to increase so that you don't lose grip on rear wheel or tip over in extreme cases. A longer frame reach can avoid having to use a stem too long as to ruin the steering handling. As for the stack, it really depends on the rider's proportions. You are among the ones that don't need additional stack at all. For those who do, they could always achieve an ideal stack with a riser, which is why high stack is not really mandatory for this fit.