I suppose if this were real, the charging warriors must all think they can glance the pike off their shield and barrel through. However, they end up glancing it to the left or right, surprising the warrior next to them who gets stabbed. They themselves get stabbed by the pike being glanced by the warrior next to them.
Assuming an equal number of front line charging warriors to pike soldiers, if charging warriors all glanced left or all glanced right, there would be 1 charging warrior left unharmed.
However, if every 2nd charging warrior agreed to sacrifice the guy between them and both glance towards him, 2N / 3 warriors could survive to fight on. The middle guy would also have to agree to not attempt to block the pike. He'd have to just run into it. But that is optimal I think.