See, this is the premise that libs work from that screws their thinking up. This assumption is that reducing spending takes money out of the economy. That's patently false.
Where does government get it's money? It takes it out of the economy. So, if we reduce spending, more money will be left in the economy. Her premise is correct. I doubt that she's bothered to flesh it out to any kind of workable plan. You are correct, I haven't spent much time listening to her. Nor have too many other people, apparently.
Simplistic analysis.
You have to ask where the spending is going and where the money is coming from. On the second part, your right-wing orthodoxy is wrong: currently, that 43% is NOT coming out of (from) the economy, it's mostly coming from overseas. The result is that a huge amount of money would in fact be sucked out of the economy. And the suddenness of it would set off a crash like we can hardly imagine.
Something else involved that I haven't heard even Gary Johnson address would be the sudden dumping of a horde of people into the ranks of the unemployed.
But this is a blind spot of conservatives: they conceive of the U.S. economy as a closed system. In a closed system, cutting taxes for the rich would in fact create some jobs. In our open system, it creates jobs, too, but it creates them where labor is cheap -- overseas. Thus cutting taxes for the rich has the effect of
cutting American jobs.
Here's a far better idea: reduce the pay of all federal employees to no higher than the median.
And here's one that gives me the creeps to say, but raising the minimum wage to $12.50/hr. Unfortunately, that has one weakness: too much of it would be spent on imports.
Sadly, I haven't heard any of the candidates for president show a grasp of the complexity of the matter. We have to get more money into the hands of workers (basically stop the plundering of honest labor), while increasing American manufacturing. The latter means massive tax increases on the wealthy, with deductions for new jobs created here -- Republicans like to (mendaciously) refer to the wealthy as "job creators"; well, let's give them a reason to create those jobs here, instead of overseas.
Then there are other steps needed (flat tax cuts, for one), but I'll leave that there.