Aside from the clearly poor situations, is anyone willing to post samples of the "good" and "bad" down-rezzing?
In my experience, if the colors and tonality are intact, all that's left is a level of sharpening and detail. I have yet to find a down-sampled image that just plain looked horrible from Photoshop, LR, etc. It would seem a lot of this thread is just splitting hairs on comparing a 39mp original to a 0.5mp web image and clamoring for more detail. It's the web. And if you post an image on the web, more than half the folks that see it won't even be on a color corrected monitor or anything... a little variation in detail will be a moot point, only important to you and no one else. It doesn't seem nearly worth the effort of using special programs to clutter up the workflow.
That said, I am not pleased at all with C1 Pro's JPEG output at small resolutions, they aren't anti-aliased or something, very strange with pixel mosaic patterns kind of. But if you use the special "web contact sheet" output option, the JPEGs are great. I've talked with Doug at CI, no real explanation or answer, other than definitely to use the web contact sheet option to output for web.