Originally Posted by n4pster228
is this reversible?
It depends on what you mean.
Root is reversible. You can easily unroot a stock HTC ROM. Or if you installed a custom ROM, you can flash back to a non-rooted stock HTC ROM.
Unlocking the updated HBOOT is reversible. It's not to hard to relock it.
Updating the HBOOT is reversible. It's not easy, but it's possible to flash an older locked HBOOT.
Waiving your warranty rights is not reversible. During the bootloader unlock process you are required to upload your phone's oem identifier token to htc's website. They'll know that your phone's bootloader has been unlocked, even if you revert. Your warranty is still broken.
Like I say in the guide, don't do the procedure unless you are willing to sacrifice your warranty. But once it's done, I don't know why you'd want to reverse it all. The extra control you gain over the hardware is well worth it for a tweaker like me.