OK, the laffer curve can be used to indicate tax cuts on any part of the curve, it is a theory based on recieved wisdom at the very best, and its root is presuppositional belief that low tax stimulates growth. Its actually a direct lift from some 14th century soothsayer, who had little or no evidence for the opinion either.
There is no direct empirical correlation between tax and growth, for every low tax economy with high growth, there is another one with low or no growth, and several high tax economies that have long term stable growth. According to Laffer himself you cannot use the curve to show when it is time to raise taxes. On every level it is a system used to justify lowering taxes for the very wealthy at every single point in an economic cycle - economy doing well - lower taxes to maintain economic benefits. economy stagnating - lower taxes to stimulate growth. economy shrinking - lower taxes to launch a recovery. Thats why it has about as much credibility as flat earth.
There is another one called the phillips curve which connects inflation and unemployment, again simple recieved wisdom and a justification for libertarian supply side economics, and maintaining an insecure low wage economy for a majority of workers.
There is a direct correlation between modern tax cuts and asset value increases and there is a correlation between asset value increases and unemployemt but i havent seen anything that empirically concludes a causation. But based on the lack of real evidence in the Laffer theory i could easily come to the conclusion that tax cuts actually cause unemployment.
The fact that the figures for growth, inflation, unemployment are so manipulable calls into question most economic theories that try and connect these aspects. I make the claim elsewhere that the majority of economics is simply justification of faith in a system. Even keynsian economics is largely faith based, in that the tools of the economic theory are the outcomes.
The fact that both systems are still in frquent use as tools is astonishing.