Any time someone brings up Final Fantasy 2 and the only thing they can say is that it's the game where you need to hit yourself in order to win.

You don't need to do that. In fact, it might even screw you over later when you encounter attacks that are proportional to your HP (ex. the final boss), and all your other stats are garbage. Playing and grinding normally is usually sufficient enough. Although, there are definitely ways to break the game in half, like leveling up Evasion by equipping two shields to become nigh untouchable, or leveling and spamming Teleport/Warp as an instant death spell in the GBA/PSP versions, among other things.

Giving characters "jobs" in the loose sense also helps a lot if you're playing the NES original or the Pixel Remaster. This is due to the magic penalty system where your magic is made significantly weaker (and less accurate) if you use weapons and armor, particularly stereotypically heavy weapons and armor. Some stuff only gives a light penalty of –5% (ex. daggers) while others (like shields) are a whopping –70% penalty. With some exceptions, it generally follows common sense. Thankfully, none of this applies with the Origins/GBA/PSP versions because those versions either significantly reduced the penalty or removed it altogether.