You said, "Manual says coach power switch must be on. Checked affirmative and still no go. Decided to cycle the switch and voila the slide extended."
Which coach power switch are you referring to - the salesman's switch at the front door, or the coach battery disconnect, or...?
When we had our bedroom slide suddenly become inoperable while in Houston last Fall, the wires had become disconnected from one of the slide's limit switches... which breaks continuity to the whole slide-electrical system. I doubt that's your problem, but I wanted to throw it in to think about. The wires did not appear to be loose until we tugged on them. You could have a loose wire at your "coach power switch" or elsewhere in the circuit.