It might work, but if folks are correct about the current capacity, the plug might weld itself to the jack. It would then be hard to disassemble, because the nut on the jack wouldn't come off past the plug. The good news is that the plug wouldn't fall out when you pull out of a wingover, as Motorman feared.
This is correct. With a "switched" jack when the plug is removed the contacts are in bypass internally, connecting and turning on the circuit. With the plug removed the circuit is through the jack instead, allowing for charging.
This might be the thing for some OTS ignition engines with rechargeable batteries. Plug in the charging cord disconnects the battery from the circuit. This is the same as my use with my glider.
Phil