If the above routine manages to eject the tray for the second swap and the disc is still spinning, you got one of the newer v2 GS2's that needs a different method to stop the spindle. You can load a mock code and toggle a cheat on and then off. Select to boot "With Codes" and press X to start. You will get an "Updating Codes" screen. This typically stops the spindle for about 35-40 seconds on these updated v2.x GS2's. Immediately let go of the reset button to get the tray to open, swap it in and it should boot.
If it ain't broke don't try to fix it! But, hell if you can tweak that bastard just a little bit more....hehehe.