I wasn't talking about 5 tanks.
I was talking about not getting a dedicated healer.
I was talking about 1 Tank and 4 Ret Paladins.

5 Tanks is easier for getting used to multiboxing because the chars don't take that much damage especially in groups of adds
because often every tank got the aggro of 1-2 mobs and not one is getting all the damage so healing is quiet easy because
of a constant amount of damage incoming.

In the first instances 5 tanks are doing enough damage to get the mobs down very fast. Later you need to change the
setup because of the larger amount of health the mobs got so I'd switch to 1 tank and 4 retribution paladins and generate
holy power charges with crusader strike and using these charges to keep the tank / the group alive.

I am used to keyclone so I don't know the benefits other tools like ISB got. I prefer more macros ingame and less
configuration in external tools and (tbh) I am boxing since keyclone started therefore I am bit lazy to get used
to another tool and stay with the stuff I got and I know