DOE change factors

[#1]

Is there any difference between Hard and Very Hard in the way JMP sets up the DOE? I know that there is a difference between Easy and Hard, but I cannot locate anything on the Very Hard setting.

Thanks

[#2]

Yes there is.
If you go to the Help pull down menu in JMP and use the search capability you can enter "creating split-plot designs". This should lead you to the documentation around hard to change and easy to change factors. This is then followed by the creating split-split plot designs which is then followed by creating strip plot designs. Each one describes the scenario behind the situations that would require this type of graduated treatment of the factors.
I find it helpful just to set up the design in each case and utilize the simulate responses capability in JMP to then run the analysis of the design and examine what the output model looks like in the scenarios mentioned above. Each situation is different due to the randomness differences in the whole plots and sub plots that result by specifying the factor type.
I hope this helps