No problem.

Why do you want to see your group btw?

When I am worried about pats or losing aggro I try and position my tank so the tank is looking towards the group with the mobs between the tank and the group.

This way it is very easy to see if one peels off to go hassle the group or if you get a pat add. It is not a big deal though. After a few instance runs you will almost know sub-consciously when you are likely to lose aggro.

You can also get mods that flash the entire window red when you get hit. Even if you are really focused on your tanking you are definitely going to notice a HUGE BIG RED FLASH coming from the 2nd screen.

Omen threat meter has a visual indicator like that when your threat is within 90% of whoever is top of the threat meter. I suppose it has a way to assign a MT but I haven't played with it too much though.

Mostly I tank by feel and only on tough pulls where I have to chain heal do I really need to worry about losing aggro. Even then, losing aggro is sometimes a good thing as it gives that little 1 second breathing room where no one is getting hit and the priest can get a Fade off with the GCD and resume chain healing without the tank going down.