Hubby did that in the supermarket once. Turned the corner and there was an old man with a REAL limp. I laughed out loud...and hubby kept limping!!
Unless someone expected to be followed they almost never turned around to look. The chance of being spotted came when the subject turned down a quiet street and I had to follow. At the end of the block or iff he turned the corner I'd duck into a doorway, switch the jacket and add or take off the glasses and hat.
Most of the time I'd follow from the other side of the street so I had that change option too.
I never lost anybody and as far as I know never got made.
Following in a car is a whole different deal.