2025-02-11 Throttle Stop Not Adjustable? (Carb Pivot Point why?)

Drat. Was hoping for replies.

I haven't used 2 cables for decades but I'll take a poke at this. The theory behind the use of 2 throttle cables as I understand it is for safety reasons.  The second cable allows for the throttles to be closed if the PULL cable (OPEN throttle) breaks.  
The Spring that is being referred to, allows for the two cables to be adjusted correctly albeit allowing for some mis-adjustment differential enabling the throttle-plates to close correctly to idle while still allowing the 2nd "return to closed throttle" cable to work correctly.
That's the best I got !
 

I just pulled out Christine's carburetors, I noticed the part you mention.

I can only tell you that on my bike it is tighter than the nuts on a submarine.

It has ZERO movement.

 

the service manual does show this piont has a bit of up and down movement

The answer to your question is outlined on page 17 in the Factory Service Manual. You need to read the section on throttle cable adjustments and understand exactly what the instructions are telling you to do. The Manual even states what the purpose of the "cable bracket" is and why it's there.