As some of you might know I've played a rogue intensely for quite some time after switching to a priest to see more PvE content. Recently, I've rolled a Death Knight (blood DPS/unholy tanking) which is currently level 74.
So far it seems that my DPS 'rotation' seems pretty much set in stone; keep diseases up, Heart Strike whenever possible, Deadly Strike to turn frost/unholy runes into blood runes to get off more Heart Strikes, and Death Coil during my "RP dump time". Unholy plays a little different, but the basics are still the same; I keep my diseases up, use Scourge/Deadly Strike whenever possible (depending on what I'm fighting and how much health I have), and use Unholy Blight/Rune Strike as RP dumps.
Now what I've noticed is that while reading DK info and browsing through the interwebs, people are constantly discussing addons needed to keep track of their runes. My experience with DK's so far has lead me to question why. Regardless whether I'm DPSing or tanking, it seems to be more of a case of "use ability X, else Y, else Z, else dump runic power" than anything else. I barely ever look at my runes anymore because there is simply no need to; the action bars will show me when I cannot use an ability and when I will be able to again. The only time I actually glance over at my runes is when I'm going to use cooldowns and want to have as many death runes up as possible to Heart Strike.
So my question basically is; why do people keep saying it's important to 'keep track of your runes'? My action bars seem to supply me with all the information I need to know, and they do a better job at that. Is it perhaps so that all the DK's who use addons to track their runes play without their action bars shown?