I think you hav overlooked my post...
Actually at this critical time AMD cannot afford to split up 2 different production line for Socket A CPU because they have to migrate part of the production line to produce more K8 based CPU...

That's why in order to fight with Intel in low end segment, they hav to come out with something which is suitably cheap and fast CPU.

That' why Tbred and Barton are chosen to make partially L2 Cache disabled CPU, namely Applebred and Thorton.

This 64KB Duron is based on Tbred core.
The codenamed Thorton position and naming scheme is unknown....