There is a difference between what the resolutions on PARAM.SFO do and what on EBOOT.BIN.
The PARAM.SFO is only responsible for which mode it will select, if a mode isn't available, it won't start or it will go to it's nearest neighbor (for example if you unselect any other resolution on Resident Evil 5's SFO than 1080 it will go to 720p after the launch of the game automatically).
On the EBOOT.BIN it's the actual whole mechanism of what it does internally.
3 different examples:
Final Fantasy XIII is 1280 x 720 scalled to 1920 x 1080 + MSAA @60Hz (exception the pre-rendered videos).
Tekken 6 is 1024 x 576 scalled to 1280x720 + 2xMSAA @60Hz.
Grand Theft Auto: IV is 1280 x 720 native but limmited to 30Hz and the scaller doubles the frequency.
What I tried to do is force the native value to be always 1920 x 1080 @60Hz.
But my point was also that I found intresting the fact that the visual result/glitch was the same that the PCSX emulator has since 3.55CFW shift, which means that it has to do something with it...