Note grouping options for simple time signatures in Dorico 5 are good enough, but for compound time signatures, they’re lacking. Take Bernstein’s “America” from West Side Story—the melody alternates between groupings of 3s and 2s, and Dorico only allows that without ties if you go in and change every single measure using brackets ([3+3]/6, [2+2+2]/6). The problem is made worse in 9/8 and 12/8, which I’m currently experiencing. Even changing some instruments’ note grouping with the meter popover messes up the rests for others. Can we please get an option to allow for this kind of syncopation by default in the notation options window?
This could be an aggregate time signature (without intermediate barlines) shift-M 3/4:6/8
This sounds as if you are looking for a mind-reading option, which would be nice but would be hard to program within Dorico’s conceptual underpinnings.
In a case such as this, you may just have to leave Force Duration on for long sections while inputting notes.
In this case you’d be better either using a staccato 8th/quaver rather than a staccato quarter/crotchet OR use a time signature of 6/4. If you still need the repeated 8ths to sound like 12/8, you could use a local time signature of 6/4 for the low instruments (select the relevant staff > shift+M > 6/4 > alt+enter).
Or enter the 12/8 as [2+2+2+3+3]/8 in the popover?
Though that won’t give you dotted quarter or half rests in the first part of the bar, like you have in your top staff. Hard to imagine a Notation option that could take care of this though, some things will always need a bit of manual labour.