I think Ming Tea put it best...
MARC 21, MARC 22,
MARC 23, MARC 24,
MARC 25, MARC 26,
MARC 27, MARC 20 heaven.
Whilst Roy may be far pure Scottish, I he seldom strays from unblended Scotch .
On a more serious note, what happens to the British Library if the vote is for independence? How long will it take for the Scottish library to join IFLA, and to develop a sufficiently incompatible MARC variant? SAMARC?
Long ago, in a land far, far away (from Scotland, that is), somebody said “MARC must die” 
But the Zepheira Ontology for the MARC 21 Bibliographic Information Environment (let’s call it zombie for short), shows how difficult it’s gonna be.
OK, today (St Andrew’s Day) is not Halloween (also a major year-cycle event in Scottish culture) – but I’m a late developer as well as a fan of the living/walking dead (the slow-movers, Romero-style, not the more modern Boyle/28 days later type).
Cheers (in jest ;-)