You could argue that however that story is over 3 years old. Also scottish money is technically more legal, an english pound is worth a pound, a scottish pound is a pound sterling, a measurement of quality any uk person should know that sterling silver has more value than almost all contimental
Well, the age of the story isn't important as it hasn't changed, nor does the value of the currency (though in all honesty I'm not sure what you're getting at there, Sterling Silver is separate to Pounds Sterling). Legal Tender in England is only produced by the Bank of England. There's no 'more legal' about it, Scottish banknotes are not legal tender in the UK.
That of course doesn't mean that they're 'illegal', merely that shopkeepers are under no legal obligation to accept them as payment.
*puts in monicle
For a time (not recently) in scotland you could take your pound to a back and exchange it for silver.
However at that time it wasnt a smart thing to do as silver wasnt worth much.
We're talking a long time ago (late 17th century iirc)
Where as english money you couldnt do that.
On a sidenote though i was in england last year and tried using a scottish note, the bar called the police claiming it was very badly forged, the english police see it as money cause they pressed charges of wasting police time on the bar.