Circular reference of smart lists
I'm trying to compile a list of those people who infrequently open our weekly newsletter so I offer them a change to monthly (starting with a limited number of people). Unfortunately Marketo only has an option for the minimum number of times someone has opened an email, not the maximum. Due to that I tried to make a smart list of frequent openers and then another smart list of subscribers not in the frequent openers smart list... It says that is a circular reference and won't work.
Here is the frequent openers smart list:

And the list that should include everyone not on the above list:

Is there another way to do this or is this just a limitation of Marketo?