The date of
"subject to more intensive and varied campaigning than the electorate in England (in a nationwide referendum)...Certain parts of the electorate may feel that they are less well informed about the referendum issue than in other parts of the country. Conversely, they may feel that they are not as well informed about the national and/or local elections."
Those are all reasons why confusion could be generated in a referendum.
Perhaps the most important consideration is broadcasting transparency. The Electoral Commission also recognised that
"the requirement to present balanced reporting of elections and a referendum is an especially difficult issue to manage when holding combined polls. Distinguishing between election and referendum campaign activities will be extremely difficult, if not impossible in some instances...These issues may have a negative effect on voter awareness; it will also make the monitoring of broadcasting (and campaign expenses) more difficult."
"made my views very clear to the politicians and the BBC...it was a bad move...condescending to Scotland, Wales and Northern Ireland...it would put broadcasters in an impossible position".
It is not difficult to see why. How many parties in the Scottish elections will broadly support changing the voting system? It may be two, three, four or even none. But how many will be on the other side of the argument? How can a programme that has a panel of guests to talk about the election and the referendum possibly be balanced? How can the BBC achieve balance and transparency on the referendum issue at the same time as it does so on the Scottish elections?