Seems like it could work well, especially if you have one that doesn't multiply too fast. I might give it a try on a few & see how well it works.

I do that with some of my beardeds. I find subsequent bloom is not thwarted for a year like it is when I lift the entire clump, divide and replant.

https://garden.org/ideas/view/KentPfeiffer/1259/Thinning-Versus-Dividing-in-Bearded-Irises/

Hi there

I meant to come back earlier.

It really makes sense that the flowering is not interrupted.

And in my case or rather the municipal gardeners` case they would aim for low maintenance and continuing flowering, not more plants

@seeingreen: that looks like a very informative website, thanks a lot

cheers, Lin