Huey, I either misunderstand your point or you misunderstand the Type Rating & Licence Endorsement List - to clarify:
If you carry out the training and LST on a BK117 A-1, A-3, A-4, B-1, B-2 or C-1 your licence will state BK117. Changing between any A or B to a C-1 or vice versa will require differences training.
If you carry out the training and LST on a BK117 C-2, C-2e, D-2 or D-2M your licence will state BK117(EC145). Changing between any C to a D or D-2M will require differences training (as will changing between C-2 and C-2e)
For those who haven't suffered the naming conventions on what Airbus advertise as an H145, it is technically called a BK117 D-2, also referred to as an EC145T2 in official documents, written in your licence as an EC145(BK117), is an EC45 over the radio or in a flight plan. Not surprising we get confused!
Cheers
TeeS