This is a simple "trick" to make it look like you're in a WB/party when hacking instances. Think about it - you're in Lost Vale for 2hrs+ and yet you don't even have a group? Some nosy guild member might get suspicious.
* start a new party (make sure it's open and not set to private)
* type /who altdorf (or inevitable)
* randomly ask someone to join your open party. tell them that you are testing a new mod and it won't take more than 30s (be creative and do not use this canned line)
* once they join, right-click your party and choose 'Convert to Warband'
* open your social window and check these 3 boxes
* uncheck this box
in the 'Open Parties' tab
* tell whoever joined that they can now leave your party and thank them for helping
is the result. Now they won't get suspicous that you have been in Lost Vale (for example) for 2hrs+ now and ungrouped.
Quick note - when you enable Watcher, it will give a FALSE ALARM saying there is 1 person watching you. If you leave the WB/party, it will then say 0. If you do this whole WB thing again, it will say 1. That's how I know it's a false alarm and no one is really watching me.
Good luck with the loot and try to avoid those pesky/nosy guild mates! :yuck:
EDIT: If you do not covert your party into a WB, it *might* not work. Meaning, your party icon might not show up in the guild roster tab and you will be seen as ungrouped.