Specflow versus Postsharp

We can define constraints in code via 2 ways. Writing specs versus writing contracts. I find using postsharp much efficient compared to specflow like solutions. The reason is the code written is never thrown out but actually used. I have seen companies stopping writing unit tests and specs with time pressures.

I would like to hear great arguments from TDD people why we should not abandon mass writing of specs and tests ?

References

SpecFlow

Use SpecFlow to define, manage and automatically execute human-readable acceptance tests in .NET projects. PostSharp

PostSharp adds design patterns and thread safety to C# and VB so you can avoid boilerplate and focus on business value.