No direct experience, but perhaps it would be too aggressive or "competitive" with the azaleas. There are several herbaceous plants with yellow flowers that make good groundcovers, assuming you've decided on yellow flowers for this location. For example, Chrysogonum virginianum (Green and gold), or Coreopsis auriculata (Mouse-ear tickseed).

Some links for Chrysogonum virginianum:

http://www.sunlightgardens.com/latin/C.html

http://davesgarden.com/pf/go/574/index.html

http://www.northcreeknurseries.com/Plants/Chrysogonum%20virginianum%20'Allen%20Bush'.htm

and for Coreopsis auriculata:

http://davesgarden.com/pf/go/993/index.html

http://www.northcreeknurseries.com/Plants/Coreopsis%20auriculata%20'Zampfir'.htm

and the Sunlight Gardens link again.

jengledc - Sorry, I just saw your post. We planted Hypericum calycinum in our small our front yard 26 years ago under a then very small Amelanchier canadensis with a few azaleas and native rhodos & added some daffodil bulbs. The rhodos never did anything. The others have all done fine. However, I would be very careful with the Hypericum since it does spread, enough that for awhile I considered trying to pull it all out. We did from one smaller bed & were able to get rid of it. However, the remaining section appears to be pretty much behaving itself (though slowly creeping over to our neighbor's--who hasn't complained). It is pretty most of the year & has received NO care during the entire time except to cut the dead twigs back in the coldest winters & pulling the few weeds that come up through it. You may well live nearby & are welcome to come & see (& even take some) if you want.

Great, bought some today. 2 small pots! Will be placing them around Otto Lygum Cherry Laurels. I bought the smallest sample of that as well.

Now to hope that the Landlord likes them!