A modest proposal - the Chump Change law

Occasioned by a discussion of pointless spending changes at Mr. Wadsworth's, I present for public discussion "The Chump Change Law of Parliament":

No Member of Parliament may propose a spending- or taxation-related Bill which does not change spending or tax by less than £1 billion.

In the 20 months since January 2011, there have been approximately 320 Bills before Parliament which works out at 192 per year. A lot of these are not related to spending or taxation. Let's be generous and say that we allow time for 100 taxation/spending bills. The current UK deficit is well over £100 billion. If any Bill is intended to address the deficit, and fails to change things by less than £1 billion then it is just pissing in the wind.

I'm tempted to make a variant of this rule for the Budget: the Chancellor has 1 hour to deliver a budget raising £600bn and spending £700bn, therefore every minute talking needs to relate to a minimum of £10bn of taxation or spending.