When you go couched lance you should always use the balanced jousting lance since its the longest. This means you can outlance any enemy lanceunit (apart from in tournaments where other units use joustinglance). If you hit right when normal attacking with the lance you can also achieve some sick damage, but its really hard! The outstretched arm plus jousting lance is REALLY long, but if you hit the enemy at the right point (IE when its around 99% stretched out) you can KO almost any enemy, I've had around 250% speedbonus when normal attacking, and this means hefty damage, however, I use couched lance far more often then normal attacking, sometimes my brain says "normal attack" and I sort of do it on pure reflex when I see an opening.
Using polearms are also usefull in other ways! When you try to sneak in to an enemy town and get caught, you use a wooden stick (and throwing daggers), so its no problem knocking them out : )