This is incredible! Did you stick a bunch of rosettes in the soil together, or did it grow like this by itself over time? If your pics are from the same couple spots over time, I think I know the answer. If I could arrange the pics in this entry by date, that would probably become apparent.

I stuck anywhere from 1-4 rosettes in the ground and they increase like this. Only thing that messes up the cluster is a wet soggy spot in the winter so I try to plant them where they stay out in the sun year round without anything shading them.
I have several scattered throughout the garden.

Thanks for the back-story. What a great plant!