I'm fairly new to DK tanking, my guild only just cleared uld 25 last week. I've had a horirble school schedule and blah blah blah, couldnt dedicate time to 25 man raiding.
Now i've gotten all that behind me, and i'm looking to get into taking in 25 mans. I've been and done all of naxx 25, as MT from start to finish a few times and i think i'm starting to get the hang of it.
I've got most of my abilities set to runestrike macros, which upped my tps considerably. But i noticed it still tends to hover around mid 3k with 4.5k spikes. Reading around on the forums this all seems "normal"