I've had my Peel w Boyer start up with key going in/out store in few minutes.
There have been a least two others on other lists report same thing. Rare but happens. We discussed how to try it on purpose by easy kick of engine over to prime a charge then send power to Boyer by key on or kill tap with key on.
Other have had a startle by a warm engine fire a good cough when key turned, or of course a loose connection jostled. Old air craft used this method.
I've hand started both Combat just to see if I could, when they were in one swing start condition w/o back fire. They had full compression so full boot slam better.
I am not good at sitting and starting, my my bud Wes does it routinely on his '71.
You could poll the list I'd bet you get a few reporting hand starts for fun.