Deflation is not that hard, just dampen social security. Or stop half of military contracts and half of infrastructure spend. Or just go to the federal budget and do anything to reduce it by > 30%. You'll have a deflation (a recession) in a month, even before those changes actually go into effect.
classic HN backseat driver - everything is easy, "just" do XYZ.
You can also jack up taxes and start paying off govt debt instead of spending it on something new. Would have similar effects.
If you think I'm wrong please write why or post a link with some economic thought, would be curious to read.
Edit: I think I understood it. You mean that broad, "macro-like" allocation would prohibit shenanigans with assets in narrower domains, like for example when a congressman successfully pushes a particular drugs-related law that has very big impact on a some particular pharma company. It is more realistic that they can change a single paragraph in some act than they can throw out 30% of the federal budget to "finally start paying back our enormous national debt".
Causing a deflation is very hard, unless possibly if you control the fed.
And that's for the government as a whole. I'd be very surprised if an individual senator can't affect that meaningfully.
Compare that to the current system where a senator hears about huge news that will move individual stock prices next week, and can easily make huge profits.