Er.....
JC: With the greatest respect; have you ever BEEN to a General Assembly?
The LHC is a ceremonial role and has no function in the deliberations of the commissioners.
I've been to four Assemblies - three as a commissioner - and also been a member of both the Practice and Procedure committee (The outfit which administers the standing orders of Assembly) and the nominatons committee (which appoints the Moderator designate for the following year, and interviews the palaces' recomendation for Lord High Commissioner designate.
Can I refer you to the "Practice and Procedure of the Church of Scotland (Cox) - you can download it if you wish, but given that, in book form it is 1670 pages long, it might take you a while.
The monarch has had no say in the governance of the Kirk since the disasterous 'Wars of the Covenant', when the later Stewart monarchs tried to interfere in the Kirk by imposing Episcopacy. That started what the English mistakenly call the 'English Civil War.'.
Since then, the Kirk has been free of state interference, and, unlike the CofE, is not established, and nor should it be.
When on 'holidy' in Scotland, the monarch attends the local kirk. The present monarch DID try to intervene inthe choice of a minister when the congregation at Crathie, near Balmoral, fell vacant in the early 1970's. THe Kirk Session politely, but firmly, informed her that this was none of her affair, and to keep out of the process.
That was the last time the palace has tried to influence the kirk in any way.