This thread is hilarious. You guys are arguing over 6 in one hand and half a dozen in the other. Both of you want 2/3 of the plays to be running plays, aka 66%. This should typically lead to a fairly balanced offense in terms of yardage assuming one aspect is not horrible. Imagine 75 actual offensive plays. 50 are running and 25 are passes. At 4 yards per carry that would be 200 rushing yards which would be a great stat. If Dak completes about 65ish % of the attempts that would be around 18 completions. That would only take about 11 ypc to have a balanced attack that calls 66% running plays.
Like coach said you can't control the yardage but that's something you gotta consider when gameplanning. It is very plausible that running it 66% of the time would be a balanced offense yardage wise.