I actually picked up a couple of cow shoulder blades and did some testing. Yes, 2 blades out penetrate 3 blades by a 2 to 1 margin at least. However, you must be using heads made of quality steal or the edge rolls over, especially single bevels.
Long 4 blades, small bleeders, out penetrated 3 blades. But, the bleeders are generally so dull once through the bone that I doubt they will cut butter.
Heads with a rockwell hardness over 54 tend to break. Heads that are to soft have points roll over, that includes tanto tips.
Skinny shafts or shafts with a smaller diameter than the broadhead ferrule, also increased penetration by double. The same size shafts as the broadhead ferrule hang up in the bone stopping penetration.