kjbawc, it does seem there is some variance in the TCM "windowbox issue" between different cable systems, and satellite handles it somewhat different from cable. Its a mess.
I understand what you mean by the "mild" borders you're seeing: these are what I'd consider within normal spec. A thin black window frame around the opening credits of a 1930s 4:3 movie makes sense, and appropriate mild "letterboxing" on the top/bottom of widescreen films that are wider format than 16:9 is appropriate. This was the norm for TCM over many years, nobody has a problem with that. The issue that some of us are seeing is a recent development on several delivery systems: previously, TCM had no consistent HD channel feed, then suddenly "TCM-HD" became available. On Time Warner Cable and some other franchises, the recent emergence of "TCM-HD" has resulted in a a complete screwup of the older standard def TCM channel.
DVD recorders and VCRs rely on composite or S-Video output from the decoder box. Most cable channels have similar standard-def framing output on the analog taps for both their HD and SD versions: 4:3 material is presented as 4:3, and widescreen material is presented letterboxed in a 4:3 frame. Put another way, on an older CRT 4:3 television you would see 4:3 material fill the screen as usual, or widescreen material would show with letterbox borders top and bottom only. Modern 16:9 flat TVs would display 4:3 material as full 4:3 in the middle of the screen with black borders on the sides
generated by the HDTV itself, while widescreen would show in the 4:3 space with letterbox borders top/bottom and black side borders
generated by the TV itself. All that is common standard display behavior for any plasma or LCD television when connected to standard-def 4:3 or letterboxed 4:3 signals.
Where TCM has recently gone mad is the complete reformatting of its signal as 4:3 nested within 4:3, reducing the active image area by 30%. So now, old 4:3 movies appear with a huge black border on all four sides, and widescreen movies and specials appear as shrunken slits letterboxed within the newly-windowboxed 4:3 frame. When viewed on a CRT 4:3 TV, the image is reduced to unwatchable size, and on modern 16:9 TVs the set itself adds the usual automatic pillars on the sides. If you use the TV zoom to magnify the old 4:3 movies, they will appear as they should (filling the 4:3 space on a 16:9 display) but you also magnify noise and artifacts that were never seen when TCM had a proper 4:3 SD signal, and zooming results on TCM widescreen programming varies almost minute to minute. This screwed-up framing and inconsistent image size has ruined the analog output of both the existing SD channel and the newer "HD" channel, at least using TWC New York, and I've seen similar complaints from viewers in other parts of the country. The issue is consistent across my Panasonic, Samsung and Sony LCDs and both Samsung and Scientific Atlanta decoder boxes, as well as friends I've checked with.
When using the HDMI output of the decoder box to feed the TV directly, the framing accuracy improves to about 50/50: sometimes it looks like it should, often it doesn't (the most glaring example being all the Robert Osbourne and Ben Mankiewicz host segments reduced to nested letterbox within 4:3, even over true HDTV connections). Yet strangely, using an HDMI>S-Video converter patched into the DVD recorder removes all these spurious black borders and returns everything to near-normal (DVD recordings play as traditional full 4:3 or letterboxed 4:3 by setting TV display to "16:9," but look squeezed on a CRT 4:3 television). IOW, it is no longer possible to make recordings from TCM that look "normal" on both a 4:3 CRT TV and an LCD/Plasma HDTV.
Bizarre. And *really* annoying.

Although it did prompt me to thoroughly test the
generic HDMI>S-Video converter
I'd previously only used sporadically. Now, I keep it handy for frequent use, and I've grown accustomed to its effect on black level. Its amazing how quickly one learns to accept black level inaccuracies when the alternative is watching an 18" diagonal image on your 32" TV.
Edited by CitiBear - 12/10/12 at 5:25pm