I can see the landing gear concept being good for someone who is a competent rider but has a handicap with their legs.
there used to be a old rider over here that you would see riding around the car park at the end of the odd group ride.... turned out he was waiting for mates to get of to hold up his bike when he stopped as his legs would lock up and he would need help getting off, I asked how he got on at intersections etc, he used to go in slow and just edge forward until free to go, last resort he would ride on the foot paths etc....and he stayed out of town on the bike... plenty of places to ride with little traffic over here.
Something like the setup above would have helped, but there are better setups than the one above