Class static variable cannot be accessed via object instance

looks like you cannot do that; this documentation looks difinitive (emphasis added):

https://www.salesforce.com/us/developer/docs/apexcode/Content/apex_classes_static.htm

Class static variables cannot be accessed through an instance of that class. So if class C has a static variable S, and x is an instance of C, then x.S is not a legal expression.

The same is true for instance methods: if M() is a static method then x.M() is not legal. Instead, your code should refer to those static identifiers using the class: C.S and C.M().

If a local variable is named the same as the class name, these static methods and variables are hidden.