what can we learn from the "neverendum" ?

Well:
1) if you word the question right - you get a bias in your favour that has nothing to do with the issues. People will tend towards the "Yes" answer. Look at the wording - it was imposed by Alec Salmond.
2) Young people have less grasp on the history, recent or long standing, and are more likely to favour novelty. Look at the age range imposed by ................
3) When Quebec voted they got not independance but a new law (and its language) that made a lot of big corporations decamp to Toronto - redundancy! Mess with the status quo and there are unexpected consequences. Unexpected not because they were not voiced, but because the politicians valued their importance over reality. Think Banking (can we have our money back?) Look at .............
4) History repeats itself. It has to, nobody is listening. Well actually they are but they ain't the ones on a quest of self importance.
5) Would Greece be in the situation it is if polititions had not pursued a policy of giving the public what they wanted? Instead of what was prudent?

Scotland is a valued member of the United Kingdom, culturally and in friendship and we can ignore the value that is the relative share of the total tax income (more than any other region). Beware, if one province were to split - how long before London declares UDI? Eh yup - Yorkshire decided not to devolve.