I hope this is the right title of the formation. Anyway I have found this to be incredibly effective and realistic.

Okay for those who don't know the formation goes like this:

Velites in the first line
Hasati and other light infantry in the second line
Principes in the third line
Triaraii in the fourth line
Cavalry on the flanks

This tactic is number 5 in the army group list and i find it works well against all armies bar phalanx based armies. Firstly I send velites forward to pepper the enemy. hen the hasati charge and if needed the principes cover the flanks. Then once the units begin to get tire I withdraw them and charge the Triarii in and send the cavlary in against the flanks or rear.

It seems to work really well, and I was just wondering if anyone else has had success with this formation.