Actually, I remember in 2002, flying from Bridgetown Barbados with Airtours who were using manual check-in at the time and it was executed very well (A330). They had a giant concertina folder which was labelled alphabetically with pre-printed boarding cards in each slot. The seatplan was stuck on the wall behind the weigh scales.
It was quite funny, because passengers were literally choosing their own seats by pointing at the seatplan...down a bit, no, left a bit.... it really made me laugh!
I must confess I still prefer to use a DCS though
