So I just finished the WonderSwan remake of this, and many of the glitches have been fixed, especially the humans with over 99 stats. Thus, Humans are not over powered, but fairly balanced. Well, at the end, I wanted to see if they had "fixed" everything, and the saw trick still worked on God. Shouldn't we conclude from this that it is still not a glitch but is by design?
Personally, I like the poetic justice of it all, being simply ended with a chainsaw (that's the Wonderswan's item name). It reminds me of the movie "Time Bandits".
Also, on a side not, now that I'm 20 years older and replayed the game as an adult with a child of my own, one of the final side rooms with the dead children really freaked me out. It made me happy to chainsaw this false God.
But have you ever noticed Creator's death animation directly corresponds to Saw's attack animation? Saw attack is a downward slash, and Creator gets sliced in two starting from the top, which is pretty unique for a final boss death animation (most of the time final bosses melt in spectacular ways).
Makes me think that they were aware of the bug, decided not to fix it, and thought it was amusing to see God get killed by a chainsaw. Think of it as an Easter Egg.
It would be quite bothersome to do different attack animations for different cases, would it not? So they left this one, the one that looks exactly like what would happen if he got sliced by Saw. And pieces are just more than one piece, so it could very well be two pieces.