Parametric Design and Organic Circulation Paths

Hello everybody,

With this post I am trying to generate a discussion about two different design techniques, how they work, what they generate, and if a specific result achieved with one can be achieved with the other. (Ps the question is at the end)

I have always wonder how architects design parks circulation paths. Apart from the obvious (access points) what else is taken into consideration before arriving to the final curve?

Length, smoothness, number of extremes? Number of connections?

Or is it simply more of a manual and hand drawn task, maybe as Oscar Niemeyer, or maybe as Roberto Burle Marx?

I wonder how this can be achieved with geometrical operations. How can we connect two points with a curve instead of a line, and have this curve create secondary paths that serve as an optional path for the person walking, as such: