all armour types have greater effect on lower damage per hit dealers.
for example using a tatar hussar, the easiest way to see how big the impact can be is to look at units doing the lowest damage. in this case it will be hussars (12 hits up to 16 with +2MA), its also why PA makes such a big impact in the game (since damage values are always lower)
vs champs and paladins its 7 up to 8 (wheras if its only +1MA, then paladins will have the same kill rate of 7)
so anything that does less damage than a paladin will be affected by +1 MA on a hussar already (and obviously on anything with more MA than a hussar).
if silk arm is +2 MA, then a tatar CA will have the same MA as a teuton paladin (not saying its a bad thing, just funny how high it already is) it will take 20 instead of 14 hits from a hussar, thats quite a jump…