Well I have just discovered something interesting. I have been creating Voice Tags all the time.

Clearly I WAS creating the Voice tags for the individual phone numbers, but thought I was re-editing the previous one each time because I was expecting to see a list of numbers in the Add Voice Tag Screen.

I still cannot find the Voice Speed dial icon on the Start > Settings > personal Screen referred to on page 167 of the User Manual where I am supposed to be able to view and test voice tag as well as create them for applications.