As I consent that it is only a game and things shouldn't be taken so personal I have to correct/complete the statement about the gladius.
It was a short sword, but definitly longer than a dagger (~50-60cm) and they had really huge shields to parry (about 120cm in height and 60cm width).
One more thing: The shown videos are training videos and as I know out of RL experience you almost always train given moves, so you know what to do cause you know what your "enemy" will do.