> there are discontinuities in the marginal tax rate, not the effective tax rate
This is often claimed. And the whole point of the article and much of this discussion is that no, there are often major steps / discontinuities in the overall tax rate. In the US, the many ACA discontinuities just by themselves are large and do not effectively pay attention to the bottom line. For that matter, I don't know of a single country or US state that actually "runs on effective tax rate". Which might be a solution to the problem if anyone were actually looking for a solution to the problem.
This is often claimed. And the whole point of the article and much of this discussion is that no, there are often major steps / discontinuities in the overall tax rate. In the US, the many ACA discontinuities just by themselves are large and do not effectively pay attention to the bottom line. For that matter, I don't know of a single country or US state that actually "runs on effective tax rate". Which might be a solution to the problem if anyone were actually looking for a solution to the problem.