Resizing a control goes too fast with auto-scroll

When I am resizing a control and the cursor goes to the edge of the screen, initiating an auto scroll, I always find that the auto-scroll is way too fast and I end up with a massive increase in the size of my control. Would it be possible to slow this down somewhat or have the scroll speed relative to the distance beyond the end of the window?

Also, trying to scroll back up, while still resizing, can cause some weird behaviour with the new size switching between really big and small.