This is often a gripe with people at work when they lose configuration settings. These settings should be done by the user. But all too often they don't bother to learn it themselves or they do but still forget. All too often they can't be bothered to really figure it out. This is the point at which IT staff become nothing more than servants.
Anyway, he was used to seeing his contacts in a public folder in an arrangement of groups.
I could not work out how he managed it but eventually realized that this can only be done with the use of categories. You can see from the below screenshots exactly how to do this: