Well, I know it's very common, but in my humble experience, tanks & healers are the worst positions for raid leading. As a healer, you can't really stop looking at the raid health bars (i've been a healer during 2 years), and as a tank, you usually have a very bad overview of what's going on, since a big thing is usually stomping on you while you're standing in the middle of an atomic explosion.
A range DPS is more suitable for this.
But indeed, if you have to lead as well, a macro can save some brain cycles

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