OP notes "rotated, flipped, stretched or otherwise photoshopped".

The first three of these - image rotation, image flipping, and image stretching - are frequent accidental side-effects that I see in presentations of all sorts.

Users rotate images to better fit a slide in a powerpoint.

Powerpoint used to flip images horizontally if you opened a presentation on a mac that was created on a pc, or vice versa (I don't know if this still happens, but it definitely used to happen). Word will flip an image horizontally or vertically if you drag one corner too far. ...and many users stretch logos and headshots through ignorance of how to symetrically re-size an image, or because they watched too much CNN when they (CNN) were intentionally distorting the screen aspect ratio in order to fill a wide TV with a 4x3 video, or because (for some reason I don't understand) they (the users) simply don't "see" the difference between the original image and the distorted one.

The first step in correcting image manipulation - if accidental - would be promoting awareness and providing tools and training. (How hard would it be for editors to do "image checks" the same way they do "grammar checks"?)

Having said that, I have *not* reviewed the papers covered in the article. My assertion that the problem may be caused by computer idiocy rather than research malevolence may be off base...

Actually, there were 500 - 700 folks in the ballroom for a convention - only 250 or so brought their laptops.

I was tasked with allowing hundreds of users to download a PDF up to 6MB in size within 5 minutes of the start of each presentation.

The theory at first was that users would download the PDFs and use Acrobat reader to add their own notes. Ultimately, everyone used the wifi for email, and got all the PDFs at the end of the meeting on a thumb drive (or after the meeting on the internets).

Xirrus 'Arrays' are designed for what you're doing. I've used 2 4-radio Xirrus arrays to serve 240 users in a single ballroom. http://store.xirrus.com/SearchResults.asp?Cat=4