This is why Challenge Rating is Broken
Challenge Rating is broken. It says that orcs are not worth any xp against a party of 11th level characters regardless of tactics! If these orcs were using poison arrows, that did +5d20 damage, fortitude save -20 for 4/5th damage, they would STILL be worth no xp. that is stupid. Does anybody here remember a little dungeon treck called "DRAGON MOUNTAIN"? That second edition adventure pitted a party of 10+ level characters on an EPIC dungeon hack, where they barely managed to survive each session, and the vast majority of the enemy were KOBOLDS. Kobolds using good tactics, in their own environment, with superior weapons and poison and traps than standard kobolds. Because the game took this into account, people got more xp.
The bottom line is a 1 hit die monster with no asterisks (special abilities) should be worth say 10xp. If a 1st level character kills one, it is worth 1% of what he needs to level. If a 20th level character does, it is worth .0001% of what he needs to level. So what if you kill 1000? I think xp should be done the way it was in the older editions-- where if a 1 hd kobold had a bow with poisoned arrows-- save or die-- he was worth more xp than a kobold with a rusty dagger.
Anyhow, that is my opinion