HTC forcing security on all their phones, even when rooted, is an inconvenience at best and heresy in many people’s eyes. S-ON basically means you cannot write to the NAND with traditional means, so flashing ROMs gets significantly more complicated. If the bootloader is unlockable, why should they force S-ON on us? If we bought the device, shouldn’t we control that too? Their unlockable bootloaders are a bit misleading in this sense. So what do you do if you want S-OFF on your devices? Sometimes it’s simple, sometimes it’s dangerous.
The DROID DNA got its first taste of S-OFF, but don’t get excited just yet. The method is one that’s quite unpleasant. The good news: You don’t have to do a thing! The bad news: Someone else is. You’ll have to send out. Yes, the only way to get S-OFF at the moment is with a JTAG machine, which can write to your phones partitions even when the phone is bricked.
Point is, you have to send it off for a week or so, pay $45 for the service, and pay shipping to get it there. Is that worth S-OFF? And even more important, is it worth getting an HTC phone if you have to PAY to get an unofficial S-OFF method done? But the option is always open and in the source links.