A play on words, gentlemen, which seems to have gone over everybody's head and wasn't that funny anyway.

A group of groups can be considered using a Venn diagram (hence the reply to Jackie's post above). The play on words was to compare this to a van (or small truck to someuvyou), add driver and turn it into a union (or group).

As I said, not very funny and even less so now that it has had to be splained.........