Bosses in video games are meant to test you to the extreme, being a massive step up from the usual enemies you encounter both in power and importance. And, not surprisingly, fighting these baddies the traditional way is normally a damn painful experience.
Is there anyone who'd honestly say no to a sneaky little way of gaining the upper hand?
With items that are either hard to find, require an enormous grind to obtain, or just plain don't make any sense to use in battle, you can often end up trivialising an opponent who would usually have thrown you about like a ragdoll for hours on end.
Some might say this takes away the fun of squaring up against something you'd have no chance of killing in real life. You might also think it's... cheating a little bit. But wherever you stand on this, after being trounced over and over again by the same unbeatable boss, there's no greater satisfaction than pulling out your A-weapon and watching that once fearsome enemy turn to putty in your hands.
In some ways, it's a shame you can't use these items to breeze through the WHOLE game.