In spring you can cut the crowns in half. Really! and in half again!
I've done it. Years ago and they lived. Didn't bloom of course but I got 4 out of one.
It was a test done while another daylily lady (from PEI) was here.
And on an inexpensive daylily.
The following year I did it with an intro. Kinda scary doing it to a $100 daylily, but it too worked.
Haven't done it since though. Just watered daylily to help increase. When I had some summer dormancy back in May, I used Neptunes (actually made in town!!!) and water. I have increase. Not large fans but increase like I would not normally get. Not sure what is responsible. Just passing on the observation.