Thank you for those links. Just had a look. However, if it were a *Roth 401k*, wouldn't the amount on Line 9 of that form (S1 ln 15 - workplace retirement plan deduction) be zero?
What the links you shared seem to boil down to is you can't claim both a 401k deduction and a SEHI deduction on the same money, but with a Roth 401k + SEHI deduction, you're only deducting the money once.
