Ah yes, the crucial thick arm cable. What was Linn thinking with the Urika.
I have been doing some testing over the last month specifically comparing speed of some of my suspended decks with 3 of my direct drives and reached the conclusion that there is no additional rotational instability caused by belt to sub chassis interaction on the suspended decks. Whatever problem people believed they were hearing is almost certainly down to something else.
The accessible guidelines and manuals I have located so far do strongly recommend that the cable is dressed so it neither pushes or pulls on the sub chassis.
The Linn setup manuals at Vinyl Engine are in line with the copy of the manual here
https://theanalogdept.com/linn_lp-12.htm
35) Plug the cable into the arm, allowing enough slack so that the cable is not pulling on the suspension; but not so much that the cable can sag and rest on the bottom board of the turntable or push on the suspension.
38) Unplug the arm cable from the bottom of the arm. The position of the armboard should not change whether the cable is plugged in or unplugged, since this could indicate that the arm cable is pushing or pulling on the suspension. If the armboard is being pulled slightly, it is usually possible to correct this without completely re-dressing the cable by grasping the cable firmly between thumb and forefinger next to the P-clip, and pulling firmly down its entire length towards the plug. This will usually straighten it enough to correct the problem. If the armboard is being pushed slightly, it can be corrected by turning the P-clip EVER SO SLIGHTLY by pushing on it with your thumb while tightening the nut that holds it. This will rotate it a slight bit and pull on the arm cable. If this will not correct the problem, you will have to redress the cable, per steps 35 and 36.
The Peter Swain set up manual has the following which appears to line up with the Linn manuals.
"Additionally, the cable attachment at the p-clip wants to be very secure indeed IMHO, so as to
avoid any unwanted movement of the dressed part of the arm-lead within the deck, additionally the
dressing/positioning of this cable should be so it causes no resistance to suspension movement at
all, and hence no effect on suspension movement whatsoever, and we want to keep it that way!"
However Mr Pig got involved with a discussion at another forum here
https://www.lejonklou.com/forum/viewtopic.php?f=2&t=5626
ThomasOK a well respected US dealer was arguing in line with the Peter Swain approach. The forum owner came back with the following which implies at least one person employed by Linn in the 90s was promoting the concept that the arm cable prevented rotational movement
"When I took Linns courses in the LP12 and system installation in the early 90's, I was told that the arm cable orientation prevented rotational movement of the subchassis, exactly as Mr Pig has suggested in this thread. A proper arm dressing should both stop the subchassis from oscillating horizontally and let it move freely along the vertical axis."