maybe my eye's arent as good as they used to be, but I often can't tell the difference between .002 and .0002 at a glance.... I think when 1=BTC is $10,000 USD this will be more of a problem!
I think the purpose of the OP's idea is that you wouldn't need to if people adopt other names and based on seeing someone posting the symbol for Satoshis... there would be corresponding symbols for those names.
Instead of seeing .0002 you would see ¤20,000 or ¤20k