Reading the links someone can feel that any static methods are bad for testability. However it is a wrong impression- static methods without external dependencies are good for testing.
There is nothing wrong with static methods and they are easy to test (so long as they don’t change any static data). For instance, think of a Maths library, which is good candidate for a static class with static methods
Static methods which hold no state and cause no side effects should be easily unit testable. In fact, I consider such methods a “poor-man’s” form of functional programming; you hand the method an object or value, and it returns an object or value. Nothing more. I don’t see how such methods would negatively affect unit testing at all.
Alternatively you can mock anything – implemented by MS Fakes, TypeMock, JustMock and Moles. They rely on .NET’sProfiling API. It can intercept any of your CIL instructions.
See related links