Arno Pro also works pretty well. It's a little narrower, and running it one size larger gives about the same horizontal density as (W)arnock Pro, but with slightly lower vertical density. Both look quite nice. Also, BTW, both of them are actually .otf fonts.
Turns out it will display more than 3 fonts, as long as they all start with A-G. In one case I actually got it to display part of an I name (ITC Berkeley) after the builtin H names, so it seems to be indexing them, but has a very strange idea about what to display.
Overall, this strikes me as a very crufty and possibly unintentional hack. But hey, it works. Mostly.