Here's a 2001 legal review from glasgow Caledonia university which obviously favours Scottish interests: https://academic.oup.com/ejil/article/12/1/77/359040?login=t...

Here's closing remarks from the SNP on a parliamentary debate, that shows the predominant driving factor was fisheries, and (if you read the rest of the debate) suggests a lot of confusion about what was being discussed and why): https://www.theyworkforyou.com/sp/?id=2000-04-26.9.0#g58.1

Here's two extremely partisan takes by a pro Indy scot who claims to have previously negotiated sea boundary changes. What's interesting is the "northward drift" : https://www.craigmurray.org.uk/archives/2017/01/scotlands-st...

https://www.craigmurray.org.uk/archives/2012/01/scotlandengl...