Is there a Bukkit plugin that would allow a server administrator to connect as another player. By that I mean play using another user's dat file? I would like to do this as it would make troubleshooting player problems easier.
Okay then. Although it is apparently not possible through a plugin, could I try renaming their dat file to my username and logging in, or would I break something?
It is possible, but it won't change everything, plugins will still know that it is just you, a teleport would have the same effect then.