I can't think of any musical scenario where I'd find that useful
Chas.....maybe after you've paid your dues and done 10,000+ gigs in your lifetime like some of us here have, maybe then you'll think of a "musical scenario where you'd find that useful."
.....I can't even think of a venue that I'd (me, chas) be playing at where the music in THAT video would 'fill the dance floor'.
Just a suggestion, perhaps a course in "musical creativity" might help?
I think it's imperative to find a way to make the accompaniment part be more 'passive' and not dominate the performance. If you're very aware of the accompaniment in a performance, you're doing something wrong. YOU, not the accompanient, should be the focus of the performance. Strong vocals and/or a strong right hand, along with a little creativity in 'juice-ing up' (augmenting) the arrangement helps a lot diminishing the 'arranger' effect.
you state "YOU, not the accompaniment, should be the focus. Well, yes, YOU are the focus, and yes, vocals and a strong right hand too, but you're forgetting something....the machine is not working you and taking the focus, you're working the machine. So the equation becomes "vocals, strong right hand, AND milking that arranger for all it's worth as part of your performance...or do you want to sound like that fellow playing the cha-cha on the Genos and never using a drum break or rhythm change?
To quote Donny...."do whatever you have to do to maximize your performance!" Mark says: I don't care how well you play (or how good your right hand is)....you need the variety in effects that an arranger keyboard gives you.....that right hand is not just for playing great licks!