If game resolution is bigger than screen size you loose
some screen area, then it would be great the
possibility to move the displayed area in order to
leave out of the screen less important things of the
game like scores.
The resize effects do the trick but often appear
artifacts on the screen while scrolling or deforms the
image. If you use a resolution with a greater number of
lines (like 288) it's not possible to get 60 hz (while
in 15.7 khz horizontal scan). And some vertical games
are in such a big resolution which is imposible to
achieve without an interlaced mode or a vertical screen.
This would be specially useful for displaying vertical
games with horizontal monitors at 15.7 khz and 60 hz.
Take for example crackdown (although it's a horizontal
game): you could use a non interlaced 15 khz resolution
and center the screen on the playable area.
Or Trick Trap (a 224x280x60 vertical game), you could
use 320x240x60 hz non interlaced resolution for a 1:1
screen emulation leaving out the upper area of the
screen (40 lines), that is the black border where the
scores are shown. Getting this way the the full
playable area whithout any resize.
Of course this won't solve all games, but many of them.
And it's in my opinion another useful display option
great for arcade monitors.
Sorry of my poor english.