The reason I'm not using the Steinberg driver is because... What? There is a Steinberg driver?
Hold the phone...
In REAPER Option - Devices - Audio system:
(I see these options)
WDM
Direct Sound
Wave Out
ASIO
Dummy Audio
WASAPI
There is no option for Steinberg UR22.
AAhh Ooooo?! Something tells me I should look harder. Let's see here...
What if I select ASIO and I click on this dropdown button: ASIO DRIVER
Holy smoligans?! Did you see that? There's a second option that just appeared "Yamaha Steinberg USB ASIO" . This option also appears if I dropdown scroll for Direct, WASAPI, etc.
Well I'll be...
That's it. All is good. Turns out I wasn't looking hard enough. I was assuming that the Steinberg DRIVER would be an addition to the Devices - Audio system, NOT a variant of ASIO4ALL.
Thanks guys for providing the appropriate question to get me working it out.
Ok. Now back to writing better songs.