Declarer says "having none" without being asked
Suppose a declarer, when failing to follow suit, volunteers "having none" without being asked by dummy or an opponent. Have any Laws been broken? If so, what is the rectification?
Normally, making gratuitous comments runs foul of the UI laws, but in this case I can't see any potential UI issues: dummy gets no advantage from declarer making comments that may suggest plays, because declarer suggests every play to dummy as it is.
I think the behaviour may be sanctionable under Law 74A3 or 74B2, but neither seems like an ideal fit; I can't find anything else in the Laws that bans this sort of behaviour (as long as declarer does it consistently). Adjustments don't seem appropriate in this situation (what advantage has been gained?), so if this is against the Laws, I'd expect the punishment to be warnings, followed by a procedural penalty if those are disregarded. I'm not sure that it is against the Laws, though; and even if it is, maybe it shouldn't be (it strikes me as a less abusable way to prevent revokes by declarers than having dummy ask after a failure to follow suit, which is explicitly allowed).
Comments
Law 74C4? I would certainly use that one if a Defender said "Having None" to draw attention to the fact that she was not following suit.
All of those, plus 74B2.