The Scotsman reports polling which shows that more of the English support a second referendum on Scots independence, rather than oppose it. Let me offer a politically incorrect hypothesis to explain this.
I wouldn't be surprised if the English are tired of subsidizing the Scots. The U.K. government sends more money north in government spending than it collects from Scotland in taxes. In other words, the Scots are "tax eaters" instead of tax payers.
Following independence, that would no longer be the case. The English may look forward to have the Scots 'off their payroll.' And to no longer need consider Scots interests in making government policy.
The EU, which an independent Scotland would expect to join, tends to take a dim view of breakaway polities. Member states like Spain and Italy have their own restive regions whose independence ambitions they wish to suppress.
Imagine Hadrian's Wall becoming a real border, with customs posts and passport checks. These interesting difficulties the Scots seem to believe insignificant, and I'm not sure they're correct.
