#####Only instantiate one object in the controller.
This rule was the most interesting to me, and the one I initially mentally rejected, as it seems like it would often be impractical. But after looking further at how the implemented it, by creating a dashboard PORO with different methods to access multiple types of information, it is an interesting setup.
#####Each method should only have 5 lines.
About the 5-line methods rule - ff course in general it's good to keep methods as short and simple as possible, but I think that trying to squeeze every method into this rule will result in a lot of unreadable code using dense ternary statements, etc.