Do we need <dirgroup>?

[adrianholovaty]

I deliberately didn't migrate <dirgroup> from the old spec to the new one, as it seemed a little half-baked.

Could somebody provide some specific use cases for this (with notation screenshots), so that we can get a sense of the scope and any assorted edge cases?

[joeberkovitz]

The thinking behind <dirgroup> (and by all means let's debate it) was that we should have a way to capture directions that are flowed inline together in a specified sequence.

Example (the green boxes illustrate the potential dirgroups):

The rationales for this are:

• it captures the fact of there being a relationship between otherwise separate, atomic directions. Can't tell you how many scores I've seen from major publishers in which things like subito and p were just two elements that happened to be positioned next to each other.
• sequences of directions using positioning/offset tweaks alone will fall apart with the slightest reformatting
• many notation apps would be equipped to recognize this relationship by placing related elements into a single object (e.g. Noteflight would coalesce a single piece of expression text and interpret it properly).
• without it, we're temped to invent special mechanisms for gluing together text and dynamics, or text and form symbols (e.g. this proposal by @shoogle). Why not go general?

Hope this helps!