Actually there were 5 meetings, 1 hour weekday, book study; 2 on another weekday, school and service meeting, and 2 on Sunday, public talk and WT study.
I wonder if the abandoning of the book study was all to do with stopping unsupervised association amongst the JW's? Same thing with reducing the gaps between assembly sessions and the doing away with assembly food lines so as to reduce unsupervised association? If you look at old pics or video of the food queues everyone seemed to know everyone else. I think that has all gone now.