Ampersand Issue

I am using the XHTML plug in by Rick, all is well apart from some ampersand encoding.

A site I am working on uses the phrase A&E (NO SPACES - meaning ‘Architectural and Engineering’) a lot. I understand that the ampersands in that do not get encoded because line 1315 in core.typography reads

"& "                    => "& "

The plug-in works when we write A & E (due to the space after the ampersand)

So, can I add another entry to the array like so

"&"                    => "& "

or will that cause me a load of headaches elsewhere?

I ask because there is little chance of me getting them to put in the spaces when they begin managing the content.

Thanks.