H-m-m, judging from a couple of those tweets, it looks like he might need to improve his run stoppage. Of course, additional reps might very well go a long way to contributing to such improvement, so there's that also. He was extremely adept vs. the run in college.
Anyhow, Woods would likely provide a considerable upswing in our pass coverage, judging from the past performances of Heath in that function. I think perhaps the Cowboys staff is understandably slow when it comes to taking chances with starting too many rookies in the d-backfield at once.