I do not know everything about broadheads and all that, not by any stretch of the imagination... But I agree with what C2@TheLibrary said in point # 3. If the edge is not sharp enough to cut the hide on the way in, it will never cut the hide on the way out (even if it does not encounter bones). Make sure your blades are **surgically sharp**, or at least as close to it as you can get them, before you even think about going out in the field -- and always sharpen them before using them again. As for serrated edges...
The real selling point of serrated edges is that they do not need to be sharpened **as often** as straight edges; as those little points wear down, though, they do become duller and they will not cut as efficiently as a straight, smooth, sharp edge. Serrated edges are best for when a smooth, clean cut is not of prime importance -- such as when you are cutting your cooked steak during dinner.