I though I understood irregular groups and how to write them, having been writing music for more years than I care to mention. Software can only do what it's been programmed to do, meaning if I misunderstand something musically then so will the software I write. OK there's artificial intelligence and machine learning out there now and maybe we'll bring some of that to Drum Score Editor one day, but stick with me here, software only embodies the knowledge of those that specified it!
I've been thinking that an irregular group, i.e. when you have a bind (or slur or tie, they all have become synonymous in pipe band drumming it seems) and it has a number under the arc, that to me means you play the number of notes there in the time of one less than the number in the arc. I.E. a triplet has a 3 under the arc and it means play these 3 notes in the time of 2.
Clear as mud so far I hope. Well apparently triplets and the like, as you can have any number in such an irregular group are something called tuplets in the music theory world, and they can be much more complicated than my simple description above (https://en.wikipedia.org/wiki/Tuplet). I especially like the bit that says "Some numbers are used inconsistently: for example septuplets (septolets or septimoles) usually indicate 7 notes in the duration of 4—or in compound meter 7 for 6—but may sometimes be used to mean 7 notes in the duration of 8"
I have no idea how to deal with that!
In there though it talks about the compound meter, which for us mere mortals means a compound time signature. That's those where the beat note is divided into 3 underlying notes, e.g. in 6/8 time, it says there are 6 quavers (8th notes) in a bar, and the 8 means there's 2 beats (am not going to explain here, it's complex, well ... compound). So you have 3 quavers per beat. A simple time signature is one like 2/4 where you have 2 quarter notes (crotchets) in the bar - that's why it's simple!
OK we got through that I hope so back to the article - when there's a 2 used to group notes, and it's in a compound time signature it means something else - it's a duplet. And rules are different for duplets than tuplets! Duplets increase the duration of the notes grouped rather than decrease it. In a triplet it's 3 in the time of 2 therefore you are reducing the duration of each of the 3 notes to take the same time as 2 of those notes would usually.
How does this work and why the hell would you make it this complicated. The answer is it's all about temporarily shifting the time signature from a compound to a simple one. If your time signature naturally breaks into 3 notes and you only want to play 2 with the second on the half beat (note, not a third of the beat) how would you write that? Well we've all been writing it wrong, or at least lazily, probably because this stuff is hard to take in when you're learning to drum and understand music at the same time - that's a guess, I don't actually know why so many of us have this wrong, me included until now.
Let's take a well known 6/8 score ....
But look how we played that first bar, if you know this score you'll know the 2nd and 4th notes in the bar are actually played on the half beat, go on, try counting it out! It's definitely not played 1 2 3 1 2 3. It's played 1 2 1 2, with the 2 being on the half beat. But it's definitely not written that way. How we write it is where duplets come in.
How many of us would spot this in a score? I'd bet beer that very few of us would unless schooled outside the pipe band drumming scene.
Anyway Drum Score Editor is now "fixed" in that it recognises the duplet in compound time signatures and auto beam, beautify and the media studio all interpret them the correct way. Use them if you wish, it's pretty rare to see them in pipe band scores I think ... maybe your experience is different? Would be good to hear.