I was just replacing our dishwasher with a new one, and I noticed
something...

First off let me tell you in the past I have always swapped stuff like this
myself, but when we moved into this house we were just too busy and I didn't
have time to do everything. I let my wife hire a plumber to install the
dishwasher we brought from the old house and move her fancy toilets.

Anyway, I pulled the compression nut off the water supply line and it was
wrapped in pipe dope... over top of teflon tape... AND there was more pipe
dope under the tape. I stripped all that crap off the fitting with a wire
brush and installed it in the new dishwasher. Tape on the tapered pipe
thread into the machine, and nothing on the compression side from the supply
line. Amazingly it work just like it was designed.

Wadda dope!