Quote Originally Posted by Aaldaemon
It's definitely doable. Provided you have the right army and know what to do with it that's how RTW battles will go... It's even worse if you use horse archers... if you micromanage horse archers perfectly and don't get lazy... it's massacre after massacre.
It's a combined arms thing mostly, for me. Before the lines engage, my skirmishers whittle down their skirmishers, and in the case of slingers some of their elites. Then just before the lines close, my line troops hurl lots of missiles. This matters because legionaries use AP javelins, so even thrown at the front they cause carnage. Often by the time hand to hand starts, the enemy has already lost 10-15% of their force.

Then when they're up close and personal, all my skirmishers and cavalry slip around the line and get in behind them. One wing or the other usually routs, allowing me to then march my line troops around to outflank the centre.

As before, most casualties occur during the rout, not the actual fighting, if you get your cavalry onto them as fast as you can, that guarantees they don't rally and get back into the fight.