It's been a while since I looked at it, but they were often used to get the phone into DFU mode and upload data that way. Seeing as DFU mode requires the phone

It's been a while since I looked at it, but they were often used to get the phone into DFU mode and upload data that way. Seeing as DFU mode requires the phone itself to be rebooted, you'd likely notice what was going on unless you left it unattended.