Request for Interpretation of Class Rules concerning Rigging

Asked by Graham Bantock, commercial builder.

Relevant rules
 
F.2.3 LIMITATIONS
The function of items shall be limited to what is normally provided by items of their type.
F.2.4 CONSTRUCTION
(b) The position of parts, and the length and tension of   rigging, may be adjustable unless otherwise restricted.
F.3.3 FITTINGS
(a) MANDATORY
(2) Shroud fitting(s) or opening(s).
Observation
The class rules permit shroud fittings or openings (both plural).
Question A
Is it permitted to have a fitting in the form of a ring which goes closely round the mast and both shrouds and which may be adjusted   vertically between the shroud attachment fitting and the spreaders (if used)?
Question B
Is it permitted to have a fitting in the form of a ring which goes closely round the mast and both shrouds and which is fixed at some point between the shroud attachment fitting and the spreaders (if used)?
Question C
If neither A nor B is permitted, is it permitted to use alternative shroud attachment points during an event?
Question D
If shroud fittings are used, is it permitted to have openings for shrouds also (and vice versa) ?