Why would the reformed Calvinist do that? Calvinists don't have any teachings on sin or punishment, just a check to see whether or not you're a star-bellied Sneech (predestined to heaven) or one of the Sneeches with no stars upon thars (those poor souls Cauvin's little pocket deity created solely for the purpose of eternal damnation in the lake of fire).
RC stands for "Roman Catholic." You.
LOL. Usually the slander is that Calvinists worry too much about sin and punishment.
But since Calvinists, like all Bible-believing Christians, base their beliefs on the infallible word of God, they most certainly do have a lot of teachings about sin and punishment. All men sin every day. By the grace of God alone believers in Jesus Christ have been forgiven their sins by the one-time sacrifice of Jesus Christ on the cross, and thus they are saved by the righteousness of Christ being freely imputed to them according to the will and purpose of the Triune God.
But if, while we seek to be justified by Christ, we ourselves also are found sinners, is therefore Christ the minister of sin? God forbid. For if I build again the things which I destroyed, I make myself a transgressor. For I through the law am dead to the law, that I might live unto God. I am crucified with Christ: neverthless I live; yet not I, but Christ liveth in me: and the life which I now live in the flesh I live by the faith of the Son of God, who loved me, and gave himself for me. I do not frustrate the grace of God: for if righteousness come by the law, then Christ is dead in vain." -- Galatians 2:16-21
For by one offering he hath perfected for ever them that are sanctified... Now where remission of these is, there is no more offering for sin." -- Hebrews 10:14,18
"(God) hath saved us, and called us with an holy calling, not according to our works, but according to his own purpose and grace, which was given us in Christ Jesus before the world began" -- 2 Timothy 1:9 "Knowing that a man is not justified by the works of the law, but by the faith of Jesus Christ, even we have believed in Jesus Christ, that we might be justified by the faith of Christ, and not by the works of the law: for by the works of the law shall no flesh be justified.
As you illustrate, when you have no rebuttal you deflect into confusion.