http://bugs.winehq.org/show_bug.cgi?id=21708
--- Comment #20 from Stefan Dösinger stefan@codeweavers.com 2012-12-05 15:50:08 CST --- Commit 7b95df03c683e52b31d0e6a9e9e81072139c8f14 should improve the situation with AlwaysOffscreen = enabled somewhat. Depending on your application, you might run into https://bugs.freedesktop.org/show_bug.cgi?id=57842 . If you don't hit that bug, things might work with AlwaysOffscreen=enabled and my two hacks.
However, AlwaysOffscreen=enabled is mostly an academic exercise. On r200, not rendering to an FBO is faster anyway, unless the application renders to offscreen surfaces itself.