One can listen to MP3/M4A songs and M4B audiobooks stored on the desktop (iTunes 126.96.36.199) using Home Sharing via Wi-Fi on iPhone (iOS 6.1.3) or iPad. The file is streamed in real time.
It seems, however, that a single sound file (even if it is publicly available and not DRM-protected in any way) or audiobook cannot be copied from desktop to iPhone/iPad using Home Sharing, even though the same Apple ID is entered on all devices.
Copying between two desktop iTunes works just fine.
Does anybody know, what might be the logic behind it?