So what WERE they trying to do?

BTW, here is a list of people who had criticized SICP. The list is full of heavy-weights:

    Philip Wadler
    Donald Knuth
    Eric Raymond
    Richard Bird
    Paul Graham
    Guy Steele
    Robert Harper
    Matthias Felleisen
    Daniel Friedman
    Christopher Strachey
    Peter Landin
    John Backus