The D was not very good against the Jets. Romo made two mistakes against the Jets, they led to 3 points the other way. The defense shares much of the blame in the Jets loss.
Romo was the primary reason we lost the Lions game but again, the D was far from perfect. Since the offense takes the field again right after a pick 6, you can't really suggest a short field was the reason our D gave up 4th quarter points that did not follow turnovers. One came after a long scoring drive by our offense.
If you want to put it all on Romo go ahead, I'm tired of that argument. However, please don't act like the defense was perfect and don't act like they and/or special teams have not also put the offense in bad spots before. I've seen plenty of drives start inside our 10.