Re: what's the most "efficient" way of doing this?

[Frédéric Bron]

> Well, for example the very first tempo indication should be left-aligned with 
> the time signature.
> Lilypond does this [correctly] when the mark is in the Staff context 
> containing the time signature, but doesn't when the mark is placed in a 
> separate context.

OK, I have never considered that as an issue but now that you say it,
I see that one could prefer it being aligned with time signature.
Thanks for pointing this.
Frédéric