Emmanuel,
here's one little example what i do:
i got a kitchen layout, the furnuture is grouped together by their purpose, so, in this case a table with some chairs.
most of the times the 2 selected chairs remain invisible, but, to keep the table at a good size, i make these 2 chairs visible while resizing the table.
but to move the entire combination around, it's better to group it - including the 2 invisible chairs.
pic:
another example:
you have a set of wine glasses and bottles on a table. you can move them around or to another table or whatsoever, and you have some invisble items in this group (rendering time!).
things like that.
the main problem is (for me):
i always group all the furniture hierarchicaly together (per type/room etc.). so i can make them invisible in an instant to e.g. print a plan without anything but walls in the specific room.
to make it short: imho a group of furniture should not change the visibility of the childs.
macfrog
