The chicane at the west end of the Magdalene Glen path interrupts the flow when going uphills, particularly unpleasant for people with weak knees. It also forces cyclists uphills often to stop and start when there are other people going through, as it's not wide enough to pass.
It doesn't serve any useful purpose at it is on the top of the slope where cyclists are very slow anyway. As it's uphills, there is little danger that e.g. kids run out onto the wide pavement of Duddingston Pk South. Cyclists from the West are slow at this point anyway as they turn into the path.