If I found a Rare Candy, I'd use it. Still, I feel sure I've raised several Pokemon legitimately to level 100. And that's because I have never understood TRAINING Pokemon. Switching around the inventory of Pokemon is such a hassle to screw up and have it pass out. The first 2-3 Pokemon I have would be my oldest, trained by just battling every single trainer I find. All but my starter would be required to know some HM when in my party which the others don't. I had such a noob party.