In theory....... right?

Since a GD-ROM is the same size as a CD but holds much more data and the same goes for a DVD, shouldn't it be possible to read a GD-ROM in any DVD-ROM drive? In theory wouldn't this work because DVDs and GDs are just CD's with a tighter set of pits and grooves? And since a DVD holds more than a GD-ROM shouldn't any DVD-ROM drive be somehow capable of reading a GD-ROM? Lemme know your thoughts...