There is a other problem with battle elefanths aswell: the cost efficent counter to them are halbs. So if you go for halbs maybe you win the fight but then there is not much to do after because halbs are not a breakthrough unit. That means if one player goes for battleelefants the opponent must weaken his army comp alot because he needs to tech into halbs and mass procus them but there is not much he can do with them after the elefants are gone.