There's very little that gets my back up more than the cry of "It's traditional". Usually when you look into the subject of such supposedly unanswerable war cries the tradition in question has actually lasted five minutes in historical terms.
A case in point is the absolutely ridiculous "Save General Election Night" campaign. One of the arguments put forward by the Tories for this is, as written by Jonathan Isaby:
It's a tradition, dammit. The traditional British way of doing elections is to have people come out to vote and then count the ballot papers immediately afterwards. It's how we do it and what we're used to.
Complete, pompous, round spherical objects.
If you want to be really traditional about elections, they used to be held over three weeks. The 1868 general election started on November 17th. Gladstone didn't get his result in South Lancashire until November 24th.
Also, over the years, it has been quite normal for widespread constituencies and, particularly, Northern Irish constituencies, to be counted the day after polling.