I have not heard of this exactly as you describe it--matching directly into non-cardiac thoracic. There are, however, integrated cardiothoracic residencies popping up around the country (i.e. 3 years gen surg, 3 years CT), similar to plastics and vascular. I'm curious where your source of information got their information.
There are still only a very, very small number of thoracic only fellowships (memorial sloan most notably), where you can still sit for your (cardio)thoracic boards, and these training programs still have a cardiac training component.
The reason they still have cardiac training, no matter how thoracic only they are, is because of the American Board of Thoracic Surgery operative requirments.
Last year the ABTS finally changed the requirements, whereby you can now fulfill the operative requirements via one of 2 tracts: traditional (cardiac heavy) or thoracic (less cardiac, more thoracic).