We have at least three confirmations that this method works reliably, including my PW2 (running FW 5.7.4) yesterday, a KV last night, and today another PW2 (running FW 5.8.1) that have jailbreak installed over USB. Announcement was delayed due to some previous brick-causing issues, which we believe have been resolved. As always, follow provided instructions CAREFULLY, and all should be fine (but proceed at your own risk).