It wasn't accidental that Eck managed to exclude those of us currently living in Britain but not Scotland (too difficult), whilst registering 16 and 17 year olds to vote (somehow not too difficult).
But surely the decision should be made by those who reside in Scotland and who will be most impacted by the vote? If you are born in Scotland, but live elsewhere then its not really down to you to decide. Plus it's nice and easy ri say everyone 16+ residing in Scotland, it'd be a logistical nightmare to start trying to figure out other claims to Scottishness.