@ ChrisE
"House of cards" is also an expression that dates back to 1645 meaning a structure or argument built on a shaky foundation or one that will collapse if a necessary (but possibly overlooked or unappreciated) element is removed.
Favourites this week included Paul @4 and Mattrom @22 but, just pipping Seamus @16 (belated congrats on your "Clootie" win - clocked it yesterday) I'm going for