Topic what addons give an unfair advantage
Let me guess, someone killed a rare you wanted?
Addons do not provide any new information. At all. They simply display it in some other way. Someone with _NPCScan looking for a rare is no different than someone with a target macro running around spamming it.
And unfair? Hardly. You have access to the exact same addons as the other 10 million players, if you choose not to use them, that's your decision, but you can't say they give an unfair advantage if you yourself can use them as well.
Edited by Sedivy on 10/11/12 2:00 AM (PDT)
The thing is addons don't magically get information that's not already there for us.
Blizz chooses to make it available for addons, even if they don't choose to show it in default UI for various reasons (usually too much clutter, not everyone wants the info and so on).
If there is ever anything that addons are inferring information wise, that blizz doesn't want us to have, they just make that info unavailable. 3D projections of things were a good example that quickly got broken.
As Ruby pointed out, if you are looking for rares, you can run around and spam the macro and find the mob. NPCScan really makes the process much easier cause of audio/visual cues but it isn't much different than say PowerAuras wiith its audio/visual cues of important events like procs, buffs, health/mana levels, debuffs and so on. And that one got so popular/useful that they included a stripped down version into the default UI.
Going over reports and analyzing fights to see what worked and what did not work is a benifit to any class. It is a very powerful tool that gives a distinct advantage to anyone who spends some time analyzing their performance and tweaking their gameplay.
I wish more people would use if for more than a DPS or HPS meter.
Of course this is not an “unfair” advantage. The player that does their homework has an advantage over the player who does not pay attention, fairness does not come into play.