[BugsJustFindMe]

First, jumping and flickering aren't the same thing. In my experience, google maps is somewhat unwilling to rapidly reposition you if two paths are equally probable.

Second, the cost of deciding that you're in the wrong lane is very different from the cost of deciding that there isn't an obstacle in front of you. The worst thing that happens when a navigator gets your position wrong is you miss a turn and spend a few extra minutes in the car. The worst thing that happens in the other case is someone dies instantly in a cloud of blood.