General tips for specialists:
>>One very strong unit is more effective than 2 average ones. so attach specialists to your full strength veteran/elite tank or motorised infantry units.
>>Reorganise specialists from weak 2-4 step infantry units where they will do little good
>>Specialists only become active if they are in supply, so don't add specialists to any unit that is ending its move out of supply or is likely to be cut off next turn
>>Add specialists at the end of your turn, so they do not risk becoming casualties in com,bat while suppressed
Attach these to your schwerepunkt panzer divisions. Their ability to ingore river shifts in combat and undermine entrenchment makes them the most valuable attachment for the Germans
These enable units to enter and leave a ZOC - ideal attachments for a fast moving unit that needs to breakthrough to cut supply on its own. They add offensive punch too.
Good on defense as armour stoppers. Will probably come into their own as airpower increases to protect the units around them
Solid mulit-purpose attachments, beefing up both attack and defense equally. Note that the armour shift only applies on defense.