私有共享变量与局部变量/命名空间污染与性能？

Reviewing code, I came across a number of new Private Shared variables (of type Hashtables(Of String), initialized in the declaration) added to a partial class for a very large (DataContext-derived) class. This seems sensible to me in one sense because they never change, and making these shared variables ensures that they won't get re-initialized every time a function is called. However, these variables Reviewing code, I came across a number of new P