I like what you saying dark_liz, it makes complete sense if magical/mystical energy was substituted for XP. Then XP could be a different value completely, like a representation of total XP orbs collected, but obviously it never decreases with enchanting.
lol The conclusion I've come to is that Fire Aspect is half bad. You see, it's a cursed effect that causes Magical Energy Orbs to not drop from creatures because they die from the fire... but it's a broken curse that only works some of the time, lol. Actually, what happens seems to be that monsters killed by the fire from a fire aspect sword are supposed to drop Magical Energy Orbs, but for some reason, a bug no doubt, they don't all the time. So if you're using a fire aspect sword to collect Magical Energy Orbs you may get less of them than using another type of sword.
You can have them R0bbieJo. <8-bit sound> ALL MY BANE OF ANTHROPODS SWORDS ARE BELONG TO YOU. </8-bit sound>
necropost is necro from the wiki! Death by Fire/ Lava - Mobs will not drop orbs if killed by fire, lava or burning. However, if the mob was ignited by an enchanted sword, and the following burning damage kills the mob, it will drop orbs