I had a look at your AP2.jpg close-up, and I think this knob, as well as
others, can definitely use some "cosmetic streamlining". I don't like the idea
of making the cables even thicker by encasing them in flume(?), they are
plenty thick enough.
What if some kind of cap could be made, that would fit over the knobs, but
can be removed if they needed adjustment. Most of the time, once the mount is
set up, these knobs no longer need attention. How often do you adjust the
latitude knob, for example - yet it is there to cause potential cable grief.
As a test, I propose you use a wide piece of cello tape - like "shipping
tape" - and spread it horizontally across the DEC knob (you could brace the
cello bridge on each side, with a piece of shipping foam peanut, to give some
lateral support). Now do the test, and watch if the standard AP unsheathed
cable still snags on that knob. I expect it will merely "ride over it".
If that works each time, then either use tape over the problem knobs -
which can be done for permanent setups - or somebody should devise a more
solid bridging device. Something that comes to mind is a plastic strap, like
that use in a recent product for "opening the nasal passages" for suffers
trying to sleep with nasal conjestion. That kind of bridging strip, if it can
be held in place on top of the knob, would act as a "cable deflector".
I hope I have explained this clearly.