I was pretty good at sailing Captain Tom, my 26' yawl, on and off the mooring. In winter I would even sail her into the marina basin and round up to the float dock. But I could stop her four tons with a turn of line, or catch the mooring pennant with a boat hook. She'd round up there too. Not so easy with Wandering Star at over ten tons. In time I'll learn to shoot her up to the mooring, with the engine running for backup. I don't know if it will ever work as well as on the yawl.
It is true that we should always be ready for engine failure. My anchor is rigged and ready. My sails are uncovered when I cast off, I could be anchored or under sail in probably a minute.