When I got black chain oil on a white T-shirt, I just applied some good washing-up liquid directly on the stain and gently rubbed the mark with a nail brush. Then a rinse under the hot tap, then into the normal wash.
Absolutely no sign now it was ever there.
I am married but spend most of time away from home with my work. Most hotels do not have places where you can clean a bike so the bathroom is the only place to go, therefore finding a way to degrease the bath is a must. Fortunately where I am at the moment we rent a Villa so cleaning the bike outside is not a problem. You are very right that I would not be top of the Christmas card list if I did that at home, although I've taken over one of the smaller rooms inside the house to keep the bikes in when I'm away!!!!!!!!!!!!!!!!!
in the 'cleaning cupboard'. Seems to get most muck (other than dried on oil based paint,tar/bitumen etc) off most things, good for glass too. Unpainted metal or chromed surfaces will start to rust overnight if cleaned with Stardrops as it seems to remove any oil or polish - it's that good at cleaning!
I also use it for washing the bikes (and the car), but make sure that I get some polish on straight after washing .