it's a contrived example to make the math easy. you can get the same outcome with more realistic values by putting the income closer to $40k and decreasing the

it's a contrived example to make the math easy. you can get the same outcome with more realistic values by putting the income closer to $40k and decreasing the gain, or you could do the analysis at a higher tax bracket boundary. my point is that it doesn't make sense to naively tax gains as if they were income acquired in a single year. I'm not arguing for/against the specific implementation of cap gains we currently have.