As far as evolutions are concerned, they probably just realized a way to evolve certain pokemon. But I could care less, it's a video game. --- Pokemon Platinum FC: 3394-9674-0193 SSBB FC: 3867-4310-3306 (>")>-|====/
i believe that FRLG are probably a few months before R/S because bill and celio barely link to Lanette, and in R/S you can already trade with kanto.
then 3 years after HGSS happens before DPPt because Cynthia already has the Secret Potion from johto to give to the player in D/P/Pt.
also one thing that confuses me is that in DPPt/HGSS you can use pal park to bring in pokemon from the GBA game which happened 3 years earlier so that kinda throws me off. --- I ARE GONNA DEVOUR UUUUU'z