The missing the pedal while driving problem is not due to numbness. It is called Proprioception. This Wikipedia link explains how your brain remembers the position of your limbs (or in our case, fails to). https://en.wikipedia.org/wiki/Proprioception
You CAN learn to improve this missing function by practice. I bought an inexpensive backup camera on eBay along with a small video display screen. I mounted the camera below the steering wheel facing the pedals. It has an LED that illminates that area. Every time you switch feet from gas to brake glance at the screen to see where you foot is and adjust it if nessecary. After a few weeks you will improve on getting the position right the first time.