Synchronize, Field Ability, Updated in the Games?

most of us know of the Synchronizing trick to get a wild pokemon with the nature that we'd like(if not, this will be a double lesson for you), but has it always been as it is now, in Diamond and Pearl? here is my theory on how it has advanced through out the games:

Ruby/Saphire:
my theory here is that they first made the nature, but either wanted to limit it, or couldn't get it to full copasity, what was missing from this ability in the days of Ruby and Saphire? it didn't work on legandaries(i made it red in my quote), basicly meaning Ruby/Saphire isn't the game you want to try to get Latias/Latios in

Smogon wrote:

When a Pokémon with this ability is first in the party (even if it is fainted) when entering battle against a wild Pokémon, there is a 50% chance of making the wild Pokémon's nature correspond to the nature of the Pokémon with this ability. This effect does not work with legendary Pokémon.

Emerald:
from my research, the ability changed as soon as Emerald was realeased, it wasn't as good as it is now, but it let Roaming Legandaries able to be Synchronized, so in Emerald you could use Synchronize to get a better natured Latios/Latias, but guys like Rayquaza and the Regis, are still a pain to get good natured

Bulbapedia wrote:

From Emerald onwards, if the Pokémon with this ability is leading the party, Synchronize gives a 50% chance of encountering a wild Pokémon with the same nature. Strangely, although Synchronize does not have this effect on stationary legendaries in Emerald, it has worked on all Pokémon in every game released since.

Fire Red/Leaf Green and after:
finally Synchronize works on any and every pokemon in the games from Fire Red/Leaf Green, and after words, so guys like Mewtwo, Suicune, Zapdos, and the other Fire Red/Leaf Green Legandaries can get a good nature, if you just have a good natured Synchronizer first in your party, i don't have a quote from a site, but feel free to ask people who have good natured legandaries from Fire Red/Leaf Green/Pearl/Diamond/Plat., most of them got it with their Synchronizers

thanks to JLA trying to catch a Latias in his Saphire, and asking me about it, i pulled together some information on it and composed this theory on it
if i'm wrong on 1-2 things, don't flip crap, just simply tell me and i'll fix it up, i've never been a big fan of Synchronizeing pokemon, so i don't know all the facts on it 110%
and if this belongs in References not Discussion, don't flip crap, just take the 2 seconds to move it, i'm too lazy to think were it fits better

Monkey