Just as I was reading the Complete iOS Jailbreak Guide where it says in "important post-jailbreak info" about restoring from an IPSW file a probably stupid question occurred to me... Does this mean that I can restore my iPod Touch to the firmware of my choice? I recently updated from 4.1 to 4.2.1, and as it seems only a tethered JB is available for this version, could I restore the iPod back to 4.1. and then happily do the untethered JB via Greenpois0n? Would my device (with 4.1) be completely the same as it was before I updated to 4.2.1? Thanks for any input.