Using Assembly Equations to suppress a part in 2013 ?

Hello There,

So I am trying to use global equations in my assembly, to suppress a part.   Is this possible ?

Is a part not a feature in this case ?

All the parts are virtual within the assembly.  Is there a way to control the instances of a part with equation wizardry ?

Also, If it was going to work, I would expect to see something in the "Evaluates to" column ?

Thank You !

SolidworksAssemblies