It is certain that all the points that protude from the formation can kill. It is just interesting that cavalry can somehow manage to punch through all 3-4 ranks and still survive only to die to a weaker sword a few seconds later (often that happens).
One gets the feeling that charging cavalry is the opposite of MTW where Spearunits in Hold Formation eliminated any cavalry charge head on. Now it seems that charging cavalry eliminated the phalanxability.