How to handle proposed addition/correction that is nested or overlapped

[hoch]

The current workflow of proposed addition/correction works okay when these changes are not nested or overlapped.

I think we need to come up with a way to handle such case - I already can see it's almost impossible to wrap the changes with the simple markup.

cc @svgeesus @padenot @mdjp

[hoch]

8/10 Teleconference: Let's ask W3C staffs if there's any way to consolidate and purge markups.