... I discovered the high Y/low Y thing years ago on my Naish x4 kites.
The X4 originally came with 4 line bar that was a low Y or V you could call it, as in the front lines seperated just above the depower strap. Naish then came out with a modification kit so you could turn your exsiting bar into a 5 line bar and is basically same as todays setup with the front lines seperated higher up. I modified my bar and lines and tested it, with poor performances as a result.
Turned out it was aweful and I couldn't understand at the time til I saw a picture of my kite the missus took and the kite looked pinched in, icecream cone style. I test my other kite sizes and found same results, with the 20m being un-useable, 16m flew badly and 12m almost useable but still not that good. The bigger the kite, the worse it got.
I then modified my lines around until I got the Y point back down lower while maintaining the 5th line performances and the kites went back to normal.
Years later I even tried a North bar on my Core XR 17m with terrible results so clearly the Y height is very important in how much "pinch" is on the kite.
From what I have seen the Ben Wilson or Ozone bar will work fine on the Cab.
Try it and see for yourself.