Exactly, to each his own..that is the best way to put it since i dont think theres been any serious research or experiments done on this subject. But i have watched a buddy do this with his last medical grow, my opinion is he was getting a bit too nit picky..meaning he was making it way harder than it has to be, not sayin your making it harder than it has to be just stating that most people over think things when its very simple. Like i said i watched my buddy do it and i seen no advantages whatsoever. Then again it wasent an actuall experiment he was just worried about just switching them no matter how much i reassured him it would do no harm.
In my opinion i see no benifits to this and on top of that the transition will add an extra week to your grow just to change the lights gradually. I say just go ahead and switch from ur veg hours straight to 12-12.