Just seen both videos. I actually saw this thread last week but I thought it was for gen 3 only...and I've just now realized it also harvored long lost gen 2 content.
As axpj said, a dream come true. Confirmation of shiny celebi, DV being randomly generated with shiny probability being separated, and even knowing shiny mew was actually available and the only known gen 2 mew distribution!
Really amazing job, thank you very much, I've been years puzzled by those questions.
Edit: I was just thinking...IF DVs are randomly generated when the pokemon is already set to not be a guaranteed shiny, there's still the chance of it being shiny?
Also, I think this was already confirmed, but all possible shiny dv combinations can be obtained for a guaranteed shiny right?