Since I was the guy who brought this up most recently, I figure I'd be the crash test dummy.
In short, the patch works fine. Below I'll detail the steps I did to verify the Pre3 was 'clean' before patching and worked fine after patching.
After getting Hulu to work on my unlocked North American ATT GSM Pre3 using the method described for your FrankenPre 2, I decided to uninstall it to check the patch uploaded in this thread.
So I followed the instructions in the Pre2 thread, and went back to the stock Flash file. I then rebooted, and verified that Flash was working correctly on Adobe's website, but that Hulu did not work (gave the standard 'not available for your platform' message).
Then, downloaded the patch listed above in this thread, unzipped it directly into the Pre3 as specified in the instructions, and ran it per instructions, even using Xecutah/Xterm on the Pre3 itself.
The patch installed correctly (lots of text scroll in the Xterm window) and took about 20 seconds. The phone then rebooted itself, and once it was back on, I went to Adobe's website to check Flash (it still worked), and then went to Hulu to check operation. Worked fine, was watching 'Fringe' about a minute after the phone rebooted.
Thanks again for all the work.