I think it's a pretty stupid command when it comes to PVP. Could you make it so that if you are killed by another player, you can not use the /back command?
I remember in another server, my town raided another town. We plundered their chests and murdered their residents. One resident in particular followed us after coming out of hiding. None of us were aware of this until we had returned to our homes and stashed our loot. After storing my battle armor, I went outside to go mining in our town's public mine, when he leaped at me and attacked me. My iron sword tore him apart, but then he kept spamming /back. Thanks to Minecraft's glitchiness and Notch's care for his game, he was now invisible. I was being punched repeatedly by an invisible person. I thrashed about randomly, managing to kill him. Then, he did it again and this time I was killed. He looted all of my things and then teleported back to his house.
tl;dr: The command sucks when you kill a sore loser.
I remember in another server, my town raided another town. We plundered their chests and murdered their residents. One resident in particular followed us after coming out of hiding. None of us were aware of this until we had returned to our homes and stashed our loot. After storing my battle armor, I went outside to go mining in our town's public mine, when he leaped at me and attacked me. My iron sword tore him apart, but then he kept spamming /back. Thanks to Minecraft's glitchiness and Notch's care for his game, he was now invisible. I was being punched repeatedly by an invisible person. I thrashed about randomly, managing to kill him. Then, he did it again and this time I was killed. He looted all of my things and then teleported back to his house.
tl;dr: The command sucks when you kill a sore loser.