Cannot use String.Empty as a default value for an optional parameter

Question

I am reading Effective C# by Bill Wagner. In Item 14 - Minimize Duplicate Initialization Logic, he shows the following example of using the new opt

Answer 1

As of the C# 2.0 compiler, there is very little point to String.Empty anyway, and in fact in many cases it's a pessimisation, since the compiler can inline some references to "" but can't do the same with String.Empty.

In C# 1.1 it was useful to avoid creating lots of independent objects all containing the empty string, but those days are gone. "" works just fine.