Panels on flow view

I have my scores in flow view a lot, because I write many large- scale pieces.

Whenever I open the mixer, 'parts,' or formatting while I am in flow view, it shortens the wideness of the page, and the computer has to load for a while to shift it; the problem returns when I close the panel.

When you open the panel, what if, instead of cutting off part of the page and re-adjusting the score, you just lay it over part of the page, and add a horizontal scrollbar so you can acces the hidden page?

I know that's not completely flow view, but it would make things a lot faster and perhaps lag less; consider it.