The main less I take from it is that up until 2008 Labour was running a small deficit, but hardly a manic one, and for all the talk of austerity, it's actually just the government waiting for tax take through growth to return to make up the gap. Indeed, the two biggest periods of deficit are actually under the Tories ('92 and '10).
Numbers can often look good on their own, but in context they are inconsequential.Of course what your saying is right, it isn't logical that a programme of cutting everything would lead to growth. If there is less money moving in the system, why would there be anything to pay off debts (ignoring of course that money is a form of debt). For a business, it can lead to larger profit margins in the short term but without investment it ends up in catastrophe in the long term. General Motors was a great example of this when they filed for bankruptcy a few years back.