Getting 100% is really not tough at all as long as you're making some basic combos, but generally it's far, far too easy. Players should be congratulated for getting 40k after part 1, not 15k or whatever it is. But for those who don't play for a decent score, such percentages would be more hard to achieve. xD
Anyway, I wouldn't trust what RZers say. They never make any sense.