Re: hide and omit behaviour

[Noeck]

Thanks David,

>> Not sure pushing things back is part of the "\once" functionality.
> 
> It isn't.  Correct.  Plain context properties don't have either stack or
> the subproperty complications of \override, so \once\unset, as opposed
> to \once\revert, indeed works.

That explains it, thanks.

> Try looking in the manual for how to set the _style_ of tuplet numbers.
> I think this works by overriding the stencil callback, so just doing
> \once followed by whatever would reestablish the normal tuplet look is
> likely to work.

As usually, your guess is right and very helpful. That works perfectly:
    \once \override TupletNumber.stencil = #ly:tuplet-number::print

Thanks also for all other replies to my question.

Cheers,
Joram