The algorithm is correct and the Intel card in my laptop passes both test 2 and test 3.
After you set the virtual resolution the driver reduces the range of resolutions that you can choose. This doesn't happen on my laptop though and I think that this should be fixed in the driver.
1) What card are you using?
2) can you set up your screens so as to reproduce test 2 and attach your /var/log/Xorg.0.log ?
The algorithm is correct and the Intel card in my laptop passes both test 2 and test 3.
After you set the virtual resolution the driver reduces the range of resolutions that you can choose. This doesn't happen on my laptop though and I think that this should be fixed in the driver.
1) What card are you using?
2) can you set up your screens so as to reproduce test 2 and attach your /var/log/Xorg.0.log ?