So if only a cd-writer can read the ATIP, how come it can protect against any non-writer cd-rom out there (which most of us do have)?
i'm not totally sure what u mean by that line, but i'll try to clarify about atip protection. a burner is capable of reading the atip on a cd, while a non-burner can't. when u start a game up, it might check the disc u're playing from for the presence of an atip. if u're playing from a burner, it'll return the atip (if u're playing from a cdr copy), which signifies that the disc isn't the original game disc. if it's a non-burner, it can't return the atip, so the game can't verify that u're playing with a cdr copy. therefore it proceeds to allow u to play the game.
there are also programs that enable the hiding of the atip from every other program except itself, such as alcohol and clonecd.