How do I get access to another user's EUPS tags?

If user rhl has defined a user tag forJim, how do I enable and make use of that tag?

You can declare your own tags in ~/.eups/startup.py

hooks.config.Eups.userTags.append("forJim")

and other people’s tags with

hooks.config.Eups.userTags.append(("forJim", "rhl"))

The reason for requiring you to declare tags is to avoid typos:

setup -t top afw

would fail silently (as there is no tag tnp). As bad as typos to configure.