whats the difference between +CarryableCharacterGroups= vs +CarryableCharacterTemplates= ?

Also, is the M1, M2, etc necessary?

For example:
+CarryableCharacterGroups="AdvTrainingOfficer"
+CarryableCharacterGroups="AdvTrainingOfficerM1"
+CarryableCharacterGroups="AdvTrainingOfficerM2"
+CarryableCharacterGroups="AdvTrainingOfficerM3"

VS

+CarryableCharacterGroups="AdvTrainingOfficer"

EDIT: did a little testing in debug tactical. seems M1, etc are needed