First, as a user, when on a web page that scrolls and contains elements which scroll, I find it terrible behavior to scroll the parent of an element when it has reached it's end. To be clear: a page that is 1000px high with a window that is 700px high will scroll. This page then has an element that is sized to 200px high with 400px of content scrolling inside it. When you place your mouse cursor over the 200px element and scroll, the content in that element will scroll. When you reach the end of that content, and the mouse cursor is still hovering that same element, the page will then begin to scroll.
I find this behavior insane and terrible, am I the odd-ball or outlier on this? Or do others also find this at least irritating or problematic?
Related but not addressed here is the issue of scrolling down a long page and a scrollable element becoming focused by moving under the stationary cursor and then acting on the scrolling event?
Is there just a bigger problem of bad user experience from nested scrolling?