Again, thanks for this useful contribution to this thread and the task faced by the OP. Another irrelevant and useless waste of thread bandwidth.

The only time derailleur springs get distorted beyond the yield point is when the derailleur has been in a crash or ended up in the spokes, which is easy to determine. I've pulled hundreds off bikes, most irrecoverable.

Again, please enlighten us with your deep experience in recovering rear derailleurs as in the video, and operation that I've done successfully dozens of time.