This new variation on linked haiku sequences is explained by its innovator Peter Jastermsky. Try writing some yourself with a trusted partner and discover how addictive this form can be. This excerpt is copied from the Frogpond website:
__________
This essay will offer a brief history of the split sequence, with examples of collaborative and solo versions, as well as a brief how-to primer on writing a split sequence at the end.
I created the split sequence form in 2017. Having just written a selection of haiku and senryu, I looked at the poems in front of me and asked myself, “What would happen if I did this?” I took one of the haiku, split the three lines apart, and placed a haiku between each of those three lines. The line format became 1/3/1/3/1/3. After some tweaking, and adding a title, I realized that I had created a linked piece of some kind. But what was it?
Garry Gay created a linked verse form, the now famous rengay, in 1992. Perhaps the aspect that has been rengay’s staying power is its communal aspect. My 2017 discovery is also a linked form maintaining certain elements of renku. Over time, the rengay caught on with poets, and that communal form is strongly being written 30 years later. Linked verse brings us together. So let’s share a split sequence!
A split sequence starts once an original three-line haiku is picked that you judge will be suitable in its individual lines to split into thirds.
. . .