Some people will wonder why it has taken so long.

The moves by senior Nationalists to encourage supporters to modify their approach in internet debates and other forums are clearly welcome.

For months now the debate about the independence referendum has been carried on in some quarters with a level of vehemence which is near-toxic. For those who favour independence there is a name for this phenomenon – cybernats. Their counterparts in the pro-Union camp have been dubbed unitrolls.

It is fairly futile to debate which are more numerous, or cause most offence. The question is what impact does it have on constructive debate when anyone putting forward arguments backing either a Yes or a No vote in next year's poll can expect personal abuse to be dished out on websites and all manner of mobile social media?

Those who would otherwise contribute to this most important of national debates will give up if their contributions are shot down in abusive flames. It is damaging to the cause of the SNP and others who favour a Yes vote when some attack pro-Unionists as anti-Scottish, or berate commentators for being Unionist mouthpieces. Likewise, it undermines the credibility of Better Together when crude slurs about nationalism are used to equate support for independence with, for example, fascism.

Both official campaigns insist those who voice such opinions are not members and the campaigns have no responsibility for their views. They could do more to distance themselves.

Senior Nationalist figures are being encouraged to challenge the worst offenders directly. This is to be welcomed. Pro-Union voices should be similarly self-moderated. That means more than just challenging the most outspoken voices on Twitter, Facebook and other websites where people gather to debate and comment.

Leading campaigners and politicians must be aware the stances they take are likely to be adopted by supporters and magnified and amplified in ways which can generate far more heat than light. They should be careful to lead debate in a responsible manner.

The irony is this comes at a time when the scope for rational, enlightening debate is growing. There is a positive momentum, after this week's sudden consensus on key issues including the wording of the referendum question and campaign finance.

Most Scots are looking for clear, compelling arguments to help those who have yet to decide to make up their minds about the best way forward. They are looking for facts about what a vote for independence – or one against – would actually deliver. Against this background, nasty personalised arguments are deeply counterproductive.

If a loud and angry dispute breaks out in a public place, some will join in or intervene, but the vast majority will steer clear. It is the same online. Genuine supporters of either outcome should behave as if they were canvassing face-to-face, or they will surely alienate the very people they aim to convince.