[justinator]

Technically you're correct (the best kind of correct!) but I don't know if I'd be under the opinion that somehow doing a 5x5 (or, whatever) of Deadlifts is going to positively effect your cardiovascular system in a training sense, to the point where doing separate cardio is unnecessary.

Depending on the exertion you put forth, a different energy system is going to be utilized by the body.

* Deadlifts: ATP Creatine Phosphate

* Cardio: Aerobic

[hammock]

I suggest you read Tactical Barbell and TB 2 the conditioning guide(search for PDF). Contrary to popular wisdom, the two systems are not independent of each other

[justinator]

No, I didn't say they were. The point being is that you're not going to get great aerobic conditioning from deadlifts when compared to any other specific aerobic activity, like running.

That shouldn't even pass the sniff test, yes? If you would like to test the theory, I'll run for 5 weeks, you deadlift, then we'll test our aerobic thresholds (or whatever else you'd like to do!) :)