Not relevant. The carbon in our feces came originally from the environment and will eventually return to it whether it is burned or decays.
No net increase in carbon.
As opposed to fossil fuels, which add carbon that had been locked up below ground for megayears. Net increase of carbon in the ecosystem.
We can argue about the effects of adding carbon by burning fossil fuels, but not about whether it happens.
Will there be a new version every two years, with some being actual downgrades of the previous model?
And still, the EPA would never allow the burning of the poo without proper permits and treatment of the combustion gasses and the residual ash.
Is it a neat idea in some third world country with limited sewage and power generation capabilities? Yes. Would it ever be allowed to function in the United States with our EPA laws? No.