What inspired this wish list request?
Often times a split plot design cannot be completed in a single experimental session. Multiple sessions over multiple days are required (examples: firing of a ceramic, melt tanks, acid baths, or other hard to change factors with time and cost change-overs).
What is the improvement you would like to see?
Consider adding an option for blocking (Days or other periods, batches of raw material...) for split plot design when factors in the design are identified as hard-to-change.
why is this idea important?
Ease of use. Blocking of a split plot can be done but is not intuitive; requires one to know how to manipulate/trick the software by using a categorical factor and doing some manipulation of the resulting design. Current version of jmp is 17.1