Let me try to explain. Let's say you have a textarea element which has DOM-state (value, scroll-position). And let's say you change the value through your render-framework. With the vdom approach, only the value component of the DOM-state is modified. With the non-vdom approach, you're creating a new textarea element, and set its value. Its scroll-position is lost, unless you keep track of it.
Now with VIDEO elements, things are more problematic. If you recreate parent-nodes of a VIDEO element, the video will stop playing, or will flicker, or jump back to the beginning.
> With the non-vdom approach, you're creating a new textarea element, and set its value.
This isn't necessarily true. In fact, it's not true of Surplus and Radi.js, which is partly why they're much faster than every vdom framework out there.
Now with VIDEO elements, things are more problematic. If you recreate parent-nodes of a VIDEO element, the video will stop playing, or will flicker, or jump back to the beginning.