Accepting the inherent limitations of verbal contact, one must realize that probably no more than thirty per cent of the original information arrives as intended. Usually the percentage is much less than this.

A much better approach would be to communicate as if communication is (almost) impossible. This is more realistic...

Maybe that is an exaggeration, but realizing that what you are saying is not necessarily what they are hearing is a healthy check on yourself.

I wonder how much of this message got across to the reader.