I think it was probably a Friday meeting, I had one toddler and one on the way and needed to get back. If I'd gone by air I'd have got no further than Manchester Airport. If I recall, the NF saved me a night in a hotel in Brussels so was not that expensive and I could probably leave Leeds after work on the Thu. So, as with the sleeper trains which are making a comeback in Europe, it did work for me as well as being something I wanted to do having stood by the tracks at Dulwich and watched it go by in the 50s.
I've often thought about going to Paris by the old route as recommended by the Man in Seat 61, but it seems to be very difficult now with so little foot passenger travel on the ferries.