I would say this method is true for approx. If a nonlinear system is used for post, it would typically be an Avid Symphony, Quantel Henry, or similar non-compressed system. The networks indicate on their delivery requirement handouts that the masters they receive be of the nature as described above. Expect more and more use of Symphony type nonlinear systems, but don't expect the four networks to back down on their delivery of full bandwidth masters. And with the evolving 24 frame editing and transmission schemes, in higher resolution, tape will continue to be the major medium for editing and air, even though the current lossy MPEG2 compressed HDTV system mangles the signal delivered to your home.
Film is a high resolution capture medium.
However, the quality is kept as high as possible in the post environment, through non-compressed systems, till air. Just my thoughts and opinions. David C. Crosthwait President, DC Video 177 West Magnolia Blvd.