Enemy Cavalry unit can break my phalanx formation.

[tndgu]

note: I have KAM's alternative phalanx pike mod, but even without so, the same problem was happening and I have no idea how to prevent it.
Here, in this battle, I have 2 lines of phalanx infantry in formation stance, 2x on the front, 3x right behind them JUST IN CASE if enemy pass through, and all of them are healthy, in formation. However, as you can see, enemy light cavalry can just pass right into my solid wall of spears and go behind them and completely break my line.


The same thing happened twice on my other campaigns where I had levy pikeman and they routed because enemy light cavalry just pushed my pikes without dying and destroyed my formation.


How can I prevent this from happening? It's pretty annoying. Is it game related issue or am I missing some kind of tactic?

[MeiguoJinjang]

I am playing with medium units and the default 5 rank minimum; also using KAMs 2 submods (since yesterday).

Formations in TW games just seem kind of porous. But at 5 ranks deep they won't simply pass through. Some will get caught in the middle, but it is also virtually impossible to come out the other side alive.

Also, this porous nature works both ways. So, if you fail to pull a cavalry charge back quick enough, they get tied up in whatever they charged, and can often be very hard to get out/extract.