Ask him, he is usually happy enough to answer questions.
I used 5.6 in beta, and I've been using the release version with my a850 and a700 with good results. I have several custom tone curves loaded, but I normally use the Adobe standard curve.
I think I got it ...
When Phil says, "... incorrect for edited ARW images ...," then he means, edited in ExifTool. Editing a file possibly means changing its length. And the problem with Adobe tools obviously is, they have got the offsets to the various fields inside an ARW raw file hardcoded inside so they cannot properly handle edited (i. e. non-standard-length) ARW raw files.
Okay, raw files usually are considered read-only. But it seems Adobe is able to handle edited copies of other kinds of raw files, so not being able to handle edited ARW files specifically seems to be a bug indeed.
the problem with Adobe tools obviously is, they have got the offsets to the various fields inside an ARW raw file hardcoded inside so they cannot properly handle edited (i. e. non-standard-length) ARW raw files.
I don't have access to the source modules of Adobe tools, but I can assure you, that this is not the case. There is no "standard length", and there are no fixed offsets.
It is unclear to me from the description what the issue is. My questions would be:
What in the ARW file, precisely, is being edited? The XMP in a sidecar? Other metadata in the ARW file itself? If so, which ones?
When the description says, "the tone curve to be incorrect" -- which tone curve? The Camera Raw tone curve? If so, which one? The point curve? The parametric curve? Or are we talking about the in-camera Sony curve presets?
Phil said he submitted a bug report with Adobe which you may have seen, but we wouldn't have. My interpretation of what he says is the white-balance is being interpreted wrong in files EXIFtool has monkeyed with, because EXIFtool may insert data into or remove data from the ARW header thus changing where the "tone curve" data starts, but Adobe's RAW engine is assuming a fixed offset for the "tone curve" data and is apparently getting junk which confuses what computes the WB. As far as what "tone curve" means, please discuss with Phil if this is really a mystery.
See the following somewhat cryptic mention of the problem on his forum:
"Edited images from the A700, A850 and A900 are not read properly by Adobe Photoshop CS4 Camera Raw 5.6, DNG Converter 5.6, or LightRoom 2.6 (the white balance is wrong). I have tracked down the problem and determined that the Adobe utilities are assuming a fixed offset for some data in the ARW image (bad Adobe!). Neither the Apple OS X 10.5.8 utilities, dcraw 8.99 nor Capture One 5.0.1 have any problems with these edited images."
This means, that offsets within a tag are wrongly assumed to be fixed; my comment above related to the offsets to the tags themselves.
Sorry for the confusion.