Well, a 2011 finance department report on the impact of the government's action plan in response to the global recession concluded that investments in infrastructure had a 1.6 multiplier effect but that tax cuts were the least effective. In fact, they had a 0 or even negative multiplier effect, depending on whether they were corporate tax cuts or individual tax cuts. Even the finance department recognizes that tax cuts are about the worst way to try to stimulate the economy.
On October 27th, 2014. See this statement in context.