I thought that i have answered your query but realised later that i have just clicked reply and not reply to all. The answer would have reached you but not the forum.
The discussion is on the whole. The Kanchi mutt saving Atharva Veda is one part. ( Now those 2 men have grown to around 15-20 and Atharva classes are held in Tirupathi. Looks Chidambaram also has some but need to confirm. )
The Sambandar reference is to confirm that the sub division of Vedas were well known to Tamils and the subdivision by vyasa is not just a story.