On the 7D, APS-H would ONLY be acceptable if it was accompanied by a versatile APS-C crop mode that worked properly with all EF-S lenses.
no argument there, if 7D2 is aimed at approximately the same market as 7D. Unfortunately, an APS-C crop mode would not be capable of reducing the size of the mirror, a dimmentional challenge that limits the possibility of using the short-back focus lenses with the larger "H" sensor. I haven't seen any evidence that such a challenge can be overcome. It maybe possible I don't know - I just haven't seen evidence or desire on Canon's part to do it. I'm aware that some have even modified the EF-S 10-22mm lens for use on a FF (at 10mm the mirror strikes the lens). so maybe it can be done I dont know.
maybe the body could operate in some sort of mirrorless mode to use the S lenses, but I dont' see that catching on either.
The biggest benefit, to me, of a crop mode is to reduce the size of the data transfer to increase fps, which is not necessary in the 7D world because of the dual processor and moderate pixel count. There is no IQ advantage that I can think of -- throwing away pixels is easy enough to do in post.
Assuming that the mechanical challenge can be overcome, the point of a crop mode on such a camera would be to hide the imperfections outside of the image circle of the "S" lenses. Some sort of auto-detect would be necessary, along with a dual mount capability with the white index mark that we have today. That part is certainly doable. it just doesn't seem likely to me, that Canon would do this, as it would be too expensive for the market that depends on the S lenses.
Personally, I would prefer if APS-H was left to a higher-end body, preferably equipped with a multi-point f/8 AF sensor.
yea, and without APS-C mode which this segment would not care about. The question that still bugs me is "what is the 2nd body that Canon expects the pro wildlife togs to carry"? These are the togs most likely to appreciate a 2x converter on a 600mm f/4, and would be more likely to accept the AF consequences just to "get the reach" -- and they are not to concerned about the UWA capability on a 2nd body optimized for wildlife.