I don't remember hearing that on dw20's forgecraft vids, though he did mention something similar in the newest ssp vid at 8:25. He made a cleaver and said that you could drop a mob's hp with a different sword and then switch to the cleaver because "it's the finishing blow that counts."
I know Etho explained it in one of his videos a good while back, and showed it in action. He'd get some potions of harming and toss them at his cows, then switch to his Looting III sword before the potion lands, and all the cows that died to the potion dropped extra items as if he'd killed them with the Looting sword. He does the same thing when farming string from his cave spider spawner trap on the current Mindcrack server.
I used to do it all the time in vanilla with either a bow or a fire sword. A looting 3 sword was just too precious to waste on actually hitting anything other than endermen with.
Don't know about the bug portion. But if you can locate your player.dat file. You can edit it with a program like NBTExplorer. Using NBTExplorer you should be able to locate the delete the jetpack out of your inventory. Make a backup copy of your player.dat file to be on the safe side.
Lucky i've already done step 2!Oh, I forgot. Then go and like all my posts in the forum games section. You should be done in a few days.
For the second one, I'd suggest uninstalling Java 8 and installing 7. Java 8 still has a lot of quirks that seem to break Minecraft from time to time.
Thanks for the answer! Now, where would I find the player.dat file? I assumed it would be within the pack files, then minecraft/saves/[world in question], but where do I go from there? There is a folder named "playerdata", but that one only contains a .dat file whose name is a seemingly random string of letters and numbers. Is this the file I'm looking for?
