First year filing married. In 2018, both filed single, maxed out $10k SALT deductions but got state refunds. In one case, reducing the state tax burden by the refund amount would have still yielded the maximum $10k deduction. In the other case, the deduction would have fallen below $10k. Is it accurate that in the first case the refund would not be taxable for 2019 while in the second case the taxable amount would be the difference between the $10k deduction taken and the adjusted amount? For example in case one: State tax burden in 2018 was $15k, refund was $2k so $12k of actual tax burden existed and thus would have still maxed out the $10k limit on SALT meaning the refund was already taxed. While in the second case the 2018 tax burden was $15k and the refund was $6k so $1k of the refund would be taxable for 2019?