A) - No, this does not work in any way. Pokeballs are chance and technique all the way. I dunno how this even got popular, but anyways I still do it for fun - just like J98, exept I press the button over and over!
B) No, for basically the same reason as A. However, I you use a differant ball that has a better effect, it will improve the chance.
The easiest way to catch a legendary, as I've said a million times before, is to make sure you have False Swipe handy, and an effective status problem move (Frozen, Paralyzed and Sleep are more effective than the others. Confusion does nothing.). I usually use Thunder Wave for this. Or you could simply use a Master Ball - 100% catch rate, but use them wisely.
Remember, always save before ecountering a legendary, just in case.