I'm thinking that this is Microsoft. LD passes it off to the Sysprep process after CTOS with the only way to bring it back into the LD process is through the setupcomplete.cmd file.
And another fun little wrinkle that MS has added to the Sysprep process: Windows Updates get turned off after generalizing the image. I like to have all the current updates on my base and the first thing that MS does when checking online for updates is to update the Windows Update client. This started around late summer, whenever the latest WU client was released. The way I work around that one is to not shut down the image after sysprep /generalize, but leave it running and turn updates back on before capture.