use of # in tags field, is it beneficial?

I believe I understand the use of the # symbol in text fields in distributed applications, but with my experience using IBM Rational Change and Configuration Management for a while, the "Tags" field in the tool is a special type.  It is not used for free flowing text and documentation. The values in the field are specifically used for searching and hence the use or inclusion of a # symbol is a useless.  I looked for some basic documentation on the use of the field, believing there would be an explanation of the use and recommended use of the field, but no luck finding documentation.