Funnily enough I did that for convenience when Guild Banks were introduced.
(I promoted the officer in charge of banks who had most the bank chars in his account to GL to make the transfer easier)
I did it from the popup in Guild Tab of Social panel. (gui way)
When he tried to pass it back, the option wasn't available for my name (but it was for some of the other officers)
After a bit of hilarity.. with people passing the GL seat back and forth trying to get it back to me,
we had to look up and do it from the command-line like you said.
Looks more like a bug, than a deliberate UI choice.
PS. Sorry for the derailment, thanks for the addition.