Casting about

In today's budget debate, the casting vote of the Presiding Officer was the vote that took down the Budget Bill. He said that he was casting that vote to "follow convention and opt for the status quo".

He could, instead, have used his casting vote in the same way as he did when convenor of the Rural Development Committee on the 1st May, 2001, according to the debate in chamber on 19th September 2001.

Funnily enough, it was Mike Watson who introduced the Westminster idea of the casting vote resting with the status quo to our Parliament:

Mike Watson (Glasgow Cathcart) (Lab): We have not prepared anything in advance, so we are all looking at each other. I speak in the light of my experience not only in the Parliament as the convener of the Finance Committee but as a previous member of committees in other forums and other places.
The general principle that a casting vote should not be used to effect change is broadly accepted, and I subscribe to it.

Brings a question to mind - why bother having a casting vote rather than simply amending standing orders? Surely we should trust Convenors and Presiding Officers to be able to make a judgement?

Ach well, onwards and onwards!