I CAN EDIT THE BULBAPEDIA AND YOU CAN'T
Hey Pie, I know you haven't edited in 6 years, but I figured I would give this a try anyway.
I'm trying to track down where the claim that the Odd Egg has a 50% Shiny rate in the Japanese version of Crystal came from. The details of the Odd Egg itself are not actually in the game's code itself; the Egg was generated server-side, so it seems as if it would have been difficult to know what the actual Shiny rate was.
You added the claim that the rate was 50% to the Pokémon Egg page in 2006. Do you have any idea where you got this information? Serebii, Meowth346, and UPC had listed this specific claim since 2001-2003, so I would guess it was just a commonly held belief in the fandom at the time. (I asked Meowth346, but he doesn't remember where it came from, which is fair enough after almost 2 decades.) But if you do happen to know how we know this probability, I would certainly be interested. --SnorlaxMonster 08:33, 28 June 2020 (UTC)