Re: ebjd pair
It may be the angle of the shot, but the photo below shows the "pinching" better. Notice just above the male's eye how the forehead has a pinch to it, sort of sunk in a bit. Then look at the female in this picture and notice the smooth transition from the lips to the dorsal fin - smooth all the way, highly desirable conformation.

If it does not develop and remains but a definition of the forehead bump then it might be ok, but there is a chance that it could pinch even tighter. If you cross him with a good female JD that has a smooth and round forehead then the BGs may not carry the pinching characteristic.
It is a hard characteristic to eliminate in EBs and sometimes even in BGs. Yet JDs rarely seem to develop the pinching. The EB genetics must bring that weakness to the fore. I have seen it crop up in many EBs as they mature.