rewrite nand after fable 3 corruption?

i was just thinking i have a copy of my nand (nov 2009) from my banned xbox.
i have allready updated to the new dash.
if i played fable 3 or a game with the same protection (which im not just for arguments sake) and got the disc read error and profile corruption would i be able to overwrite my nand with the patched nand from last year.
im thinking it wont be compatible with the new dash thereby fu*king up my console alltogether.
any ideas would be great
thanks in advance