Srila Prabhupada's letters

Satsvarupa Dasa Goswami: It had been the practice of the devotees that as soon as someone received a letter from Srila Prabhupada, we would xerox it and send it to all the other centers. But in 1969 Prabhupada wrote, "Letters are sometimes personal and confidential, and if all letters are circulated, it may act reversely."