Wolf Dog.........My statements are exactly correct. A single bladed broadhead with a cutting diameter of 1 inch makes a single 1 inch slice. A broadhead with two 1 inch blades makes two 1 inch slices at 90 degrees from each other thus cutting twice as much tissue as the single blade head. The more blades you add to the broadehad the more tissue it will cut when passing through an animal.

The 10X1 inch head you give as an example would not make the hole ten times as large but it would cut ten times the ammount of tissue when passing through the animal given equal penetration. However just like Garry said there is a place you come to when you begin to get diminished returns.

Another note about penetration.... The entire arrow must follow the broadhead through the hole that it creates. The more "open" that hole is the less resistance the tissue creates on the trailing arrow and fletchings.