Should the .NET folder(s) be added to the system PATH environment variable? More precisely, assuming one has the latest .NET release installed on Windows 7, should string

C:\WINDOWS\Microsoft.NET\Framework\v4.0.30319;C:\WINDOWS\Microsoft.NET\Framework\v3.5;C:\WINDOWS\Microsoft.NET\Framework\v2.0.50727;

be included the PATH? It does not seem to be a requirement for my .NET applications to run. Thanks.