Currency union

So, having watched the Daily Politics programme, I can only conclude that an independent Scotland would continue to use the pound sterling, without a formal currency union with the remnant of the UK. In the programme, Andrew Neil grilled Scotland's Deputy First Minister Nicola Sturgeon on the issue. Ms Sturgeon declared that the decision by the three main party leaders at Westminster to refuse to go into a currency union with an independent Scotland was a 'bullying tactic', and would not elaborate as to plan B. I'm beginning to get seriously concerned about the economy of an independent Scotland, something I have always (for many, many years) regarded as the Achilles heel issue. Rather than playing the silly card of bullying, I think it is time for the SNP to wake up and smell the coffee, in other words, realise what it means to just use another country's currency. I'm not an economist, but judging by what I'm hearing, it leaves Scotland seriously exposed, also to the risk of losing investments, industry and jobs. Scotland would become the banana realm of western Europe. What's plan B? The US dollar? That's freely being used by countries around the world, who are not in a currency union with the USA.