The neutral switch lowers the rev limit in neutral, and retards the ignition timing. All the different models act differently, and there are differences even among individual bikes of the same model, but I will tell you that my 450 starts much more easily in neutral, with less advance, than it does in gear. In fact, it nearly broke my foot right through my Alpinestars one morning when it was about half warmed up, so I avoid starting in gear unless it's really called for. My 250F couldn't care less one way or the other. The assertion that disconnecting the blue wire makes the spark stronger is simply false. You can try it both ways, and set your bike up so it works best for you. Like Rich said, as long as your clutch works right, you can try it just by comparing the starting in gear to how it starts in neutral.