The question is not whether the Scots are capable for governing themselves, but whether that option will give better benefits to the people living there. On the basis of the facts that seems unlikely. But facts seem to be in short supply on the Yes side.
The most important problem is that the Nationalists have no idea what they will use as a currency. They say there will be a currency union with the rest of the UK, but all the major UK parties say that won't happen. If Scotland becomes independent it cannot force other countries to deal with it. It can't make a currency union if the other side doesn't want it. Similarly, it can't say there will be no border controls because it doesn't get to choose what's on the other side of the border. The English could put up a huge fence (and may have to) and there's absolutely nothing the Scots can do about it.
As Krugman points out if they go it alone with their own currency they will be at the whims of international capital, which will not look kindly on an unproductive welfare state that is dependent on highly volatile oil revenues (and that's if they even have a valid claim to the oil).
You say that "a people who govern themselves have a chance to grow" but what if you are wrong? What if, instead, the people who are governing are incompetent and foolish? Is there something in the Scottish water that makes their politicians trustworthy paragons of virtue. There is absolutely no guarantee that Scotland will turn out like Norway. Hope is not a policy.
As for Alex Salmond, it is about him. He has divided the country already by amplifying minor grudges against the English into political issues that have split the people. If the vote is a close yes then 50% of the people will already be disenfranchised. So much for "always getting the government you vote for".
The best option would have been for a federal system, but Braveheart-ism mixed with greed and envy have take over. Logic is useless on people like you who have an emotional desire to for their own Socialist paradise.
I can only hope wiser heads will prevail.