jailbreak 5.0, save blobs, downgrade to 4.4.4 with blobs .. possible?

I have been reading so many posts here about jailbreaking old firmware versions, downgrading firmware without blobs, etc and it’s all very good but nothing seems to answer a simple question that keeps popping into my head.


We all know that the SHSH blobs are unique to each device but are they unique to each firmware version too? … could you do a tethered jailbreak with firmware version 5.0 and save the blobs, then create custom firmware version 4.4.4 using those blobs to get an untethered jailbreak? 


Blobs are unique per idevice and firmware so no you can’t