Another solution:
***
I got back from the MS store. Their lead tech fixed it. Apparently there were several firmware updates that didn't take (Remember that the latest "firmware update" actually has several individual firmware patches in it). I tried to watch the commands that he executed to reset the windows update, it wasn't the normal DISM commands that I knew. He went directory deleting, invoked windows update from the command line with extra switches, removed a couple devices from device manager, reinstalled them, etc..
He went fast. It reminded me of myself 10 years ago fixing Windows servers. The kicker was he cleaned his tracks when he was done, so I couldn't go back in history to see what he did!!! I tried to press him on the commands and such, but he wouldn't give up the information. Most of the stuff I could see (he did well to turn the screen away from me, so it was really difficult to see everything) was normal stuff, but the secret sauce was a particular directory and it's contents he deleted, and the command line switch to kick off windows update.
But in the end, firmware updates were reapplied, and my SP3 is working just fine, for now.
***
source:
http://forums.windowscentral.com/mi.../328628-rebooted-then-stuck-surface-logo.html