I had a similar dual-propulsion idea pop into my head the other day, great to see other people are thinking the same way!
I'm interested how it would be integrated into the driving experience. How about an analogue lever behind the steering wheel, similar form-factor to the semi-automatic gear change paddles you see on exotic sports cars? Around town you might have the ICE in neutral and drive the car on the paddle lever. Then when you reach the open road, fire up the ICE, select a gear and gently release the clutch while easing off the paddle. A bit of practice needed to get the hand-eye-leg coordination!
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Anthony
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