Affects Essential too.
I have been thinking about this a lot, even dreaming about how a possible solution could work. The old way of two scroll bars was a solution so that if you were near to the bottom or top then you could scroll the table = great = worked. But... why the new solution? At first I thought, nah, that's elegant but from a UI point of view, wrong, but then... by not having scroll bars on the table but rather using the browser scroll bars because the document is big (not the window) then that means you can use a scroll bar wherever you are in a long list of grades, which is cool, its an improvement. So, now the question of a solution. How to make things work now. Ok, there is a clear need to make the container of the table bigger, but it needs to not force the whole layout of the page bigger and clearly a block region cannot be to the right (or left in RTL) of the table otherwise 'where's my blocks?'. So need to put the block regions underneath the report table, keep them a sensible width and expand the report area.
Looking at the 'Clean' theme it has no 'actual solution' as the table escapes its container 'span9', you just cannot tell because there are no borders.
So as a result of this, still thinking. Anybody else have a solution in mind?