In the rest the macro does is the basic idea from Emily's blog

In the end, because there was no way to stop it, I clipped it. Then we didn't receive that fifth missile, which can do an awful WoTLK Gold amount of damage. If you repeat that many times during the course of a fight you'll end up costing you a significant amount of damage, don't you think. The best thing to do is to use an macro that has no channeling. What this macro will do is when you're channeling your Arcane Missiles You can be mashing the macro and it won't stop, it won't fire the arcane blasts until you've made sure your Arcane Missiles are dead.

In the rest the macro does is the basic idea of making it so your Arcane Blast tab targets, and when the mob has died it then clears it. There are a few useful things to put in your main building where you're mashing. I would highly recommend that you add them to your list. However, the most important thing is that you'd like to have no channeling.

You don't need to use it though you can leave it out, right, where you're going to attempt to time it right after that fifth missile is cast. Another disadvantage of making use of the macros is you're going to introduce micro gaps into your casting based upon the amount of ping WOW WoTLK Classic Gold. So every time because you're it's having to check to verify if you're channeling.