Thanks for the kind comments. I agree with you that FICA/SECA taxes should be "pretax" for the income tax. That makes total sense! However I disagree with the idea of refundable credits. These are very useful for self-employed people in particular, as we can use such credits to help offset the self-employment tax. Perhaps we could just move the concept of non-refundable to mean non-refundable after all the additional taxes?
WP- You do make a good point. Credits should be allowed against "other taxes" like the self-employment tax. But nobody should "make a profit" by simply filing a tax return. TWTP