I saw a show on the History Channel the other night about that issue. They had an engineer suit a tank up with scrap metal on the front end that allowed them to chow through the hedges. The brass said they wanted X amount over X days and they couldn't get the quota met, but it still saved thousands of lives.Tanks were very vulnerable, and hamstrung by a host of natural tank traps. They had difficulty crossing the high banks along the field boundaries, on which the hedges grow, and often could not even turn their turrets in the lanes.
Interesting to see some of the Germans perspective of that.