Just read posts 18 and 20. I haven't changed anything. We don't know how most things work. CA isn't obligated to release all info. Period. Those two posts are just my theory on how it might work (i.e. might as well work, or how it practically works, take it as you will).

More charge for an armoured horse archer versus a kataphract makes sense. Why do you think the kataphract has more armour and less charge? Think weight. Also, the armoured horse archer has a secondary lace that is armour piercing. Check this page on the unit and you'll see their secondary lance is AP.