On our trip last November, we (party of 8) were seated at seperate tables at Le Cellier. Now I know that the ADR has that disclaimer, but it irritated me b/c it seemed like they didn't even try to work with us. In fact, they didn't even tell us that we were being split, they just showed us to the two tables. They could have angled the tables so that they were connected, but didn't. Mind you this was after we had already waited around an hour after our ADR time, so my patience was already wearing thin. Eventually they moved our tables together once some other people left and they could switch a few things around a little easier. The bottom line is it does happen.
P.S. In case it's not clear, my gripe wasn't that we were split up, it was that they didn't seem to care.