I just remembered a discussion in a group about 30 or 40 years ago. Another example of the "something for nothing" fallacy...

A guy who owned a small sailboat was talking about putting a small outboard motor on it, for use when the wind was dead calm.

One of the other guys in the group asked the boat owner why he didn't just install a large fan on the rear of the boat, and point the fan toward the mid-ship sail in order to make the boat move when where was no wind!

It took the rest of us over 20 minutes to explain to the helpful man why his suggestion wouldn't work!

1977 CJ-7, fiberglass body, AMC 360 w/ headers, DUI ignition, Edelbrock intake and Holley 4150 carb, TF999, Dana 300, 4.56 gears lockers, York air comp, 4" susp lift, 2" body lift, BFG 35" M-T tires, Megashifter, AGR pump & box, REP8000 winch.