Similar to the way SPVP tournaments require a roster to enter, the Fractals dungeon should implement a similar roster. This way when someone disconnects for any reason, they are able to re-join the team as long as they were on the original roster.
This has caused countless headaches for me, because someone always seems to disconnect, and my team ends up having to 4-man the dungeon, then repeat the difficulty level if we want to continue playing with that person. The last straw was when it happened to me after Windows Update forced a restart on me at the end of the third dungeon literally less than two minutes before achieving the next rank of difficulty.
Now, I’m a level behind everyone else who i have been playing with all day.