The issue was twofold.
First, when I took the pics I had the bindings slid back to the "speed" position which makes it look like there is an abnormal gap between the brake assembly and the heel.
We all forgot that these things can be moved fore and aft but the brake doesn't move.
Second, my boots are canted, plated and shaved.
Even though the heel is within DIN specs, I could never get a solid hold down..
The area the heel contacts the binding on the 614's is a small strip of soft plastic on either side of the boot area.
I shimmed this area up about 1mm and all is well without the heel rest I made.
I'm still using the heel rest though because it gives such a positive holddown.
I've gone through all of my skis to make sure the binding is holding the boot without allowing it to rock side to side.
I have some Volkls with the Marker integrated track assembly.
The track assembly is pretty sloppy allowing the boot cuff to move about 1 cm side to side with the ski clamped down.
A couple of long screws through the heel assy and into the ski fixed that at the expense of easy adjustability.
I just got a pair of Fischers with the Tyrolia Flowflex system.
These seem pretty good out of the box.
These have a fairly large u shaped contact area that the boot heel rests on and clamp well.
I wouldn't worry about this stuff on my daily drivers but I'm critical about race stuff.
Some binding systems have gotten to easy adjustability at the expense of boot/ski rigidity.
One of my large friends tore the plastic heel track right off an Marker/AC-50 and seriously broke an ankle.
Now I know why real racers buy flat skis and use aftermarket stuff like VIST.