[vonbill]

Changing the AO unit to a regular ( full sized ) infantry squad, has no drawbacks and several advantages in the Long Campaign.
First it is more survivable from heavy artillery fire.
Second it can fight of a sneaky rear area infiltrater.
Third if it has ant AT weapons it won't get massacred by an
enemy tank that makes a rear area soft target hunt.
I have had several long campaigns ended due to Hvy Arty killing the AO on the first turn pre bombardment. Two hits from 150mm will kill a six man AO. A full size squad may survive to rout away.
Playing any allied side, The AO can come to grief from a pair of SMG armed scouts creeping up. Not to mention the invisable Japenese. If it is full sized with integral MG, it can supress and withdraw or even kill such a pest.
I agree its best not to send AO into main fray. But it does not hurt to give it better self defense ability.