Imagine that you have one group called 'London' that includes all your contacts in London.
Within 'London' you have subsets of groups such as football friends, etc.
With tags (or maybe filters) it would be easy to see find the union of 'London' and 'Footballers' but I can't figure out how to do it with Google Contact groups.
Only way it seems is by adding people into every applicable group which is time consuming.
Anyone have a way to do this?