A much better explaination for the atmospheric effect of Venus is that its surface to atmosphere boundary is effectively iso-conductive resulting in an iso-thermal atmosphere despite its much slower rotation. The point in Venus' atmosphere where the atmosphere becomes less iso-thermal, would be the point where the ratiant properties of CO2 become significant with respect to its conductive properties.
If a solution is correct, it will be correct for all applications. Think Venus.
For the direct measurement of DWLR fans, you are using values estimated to be accurate to +/- 4Wm-2, which have been proven to have inaccuracies of +/- 20Wm-2 in the polar regions, to determine the impact of ~50% of an assumed 3.7Wm-2, which may impact surface temepratures by 0.8 degrees K which is 0.3 percent of the surface temperature. And y'all think I am nuts! Caucation please!