The {@link ref label} tag generates an HTML href anchor with a CODE label:

   <a href="ref"><CODE>label</CODE></a>

This is useful, because most of the time, the label is an API name.
We'd like the equivalent but without code:

   {@linkplain ref label} 

would generate:

   <a href="ref">label</a>

If the label is missing:

   <@linkplain ref}

then it would simply print the reference without <CODE>.
Some people might prefer that use (particularly in headings, where
code can look odd).