Whooooosh Nexus, I do believe Grrrrr was being sarcastic.
As for S-Off, I believe the One X required the bootloader messing malarkey, but with the One it's perfectly simple. Once you've unlocked it through HTC Dev, going for a custom recovery is straightforward in that one sticks it in fastboot mode, then using fastboot.exe (along with the Android SDK's platform tools) one can flash a custom recovery from Windows. From here on in, it might as well be any other unlocked Android phone, with the exception that you have to visit the bootloader before one can access the recovery. Many custom ROMs put a handy "Reboot to Recovery" option in the power menu too.
Custom ROMs are no different from other phones, in the sense that one fires up their preferred recovery, then flashes the zip as normal (perhaps doing a wipe/clear of the various caches first if coming from a different ROM).
The S-On basically means we can't flash different radios, like with Samsung devices for example. However, from my prior experience this simply resulted in a lot of confusion over which radio was best, and some very poor in-call performance in some, in others, no radio at all. Which was/is a faff. It also means some largely irrelevant directories are write-protected, and not accessible.
I was certainly a little worried about going ahead with rooting this One, but it's as simple (if not more so) than my S3/One X/S2 were. If you're looking to get started, I'm finding that the following combo is working a treat:
Recovery:
CWM Touch
Rooted with flyhalf's Superuser
ROM:
Trickdroid 5.5.1
with the relevant Tweaks and Themes packages installed
it also can install the Xposed framework at flash
some lovely statusbar tweaks, including clock positioning and battery icon mods
toggles in the notification blind
more apps in the app drawer per page and per folder
different fonts
option to remove 3 dot menu bar and enable the HTC logo as a menu button
Kernel:
ElementalX
applies a nice overclock, and can be tweaked for underclocking too
Also adds USB OTG support, and game controller support, including the PS3, which I was using earlier on Vice City.
It also adds several wake modes (sweeping the capacitive keys to wake up for example)
allows the capacitive keys to be used as a notification LED)
option to remove 3 dot menu bar and enable the HTC logo as a menu button
Tweaks:
Basil3's clock customisation
Flashable Font pack (using Polentical Neon I believe).
Screenies!
One thing that's very nice about working with Sense ROMs, is that all your settings, homescreen layouts and apps are saved through HTC's backup tool and Dropbox, so even after a fullwipe, firing it back up means you're soon seeing familiar things again

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