Emissions are a real thing. It takes time for bio-accumulation. That said, I wonder what the NET pollution is from all the energy that went into the engineering and manufacturing of emission equipment. Those engaged in all this extra activity consumed energy, emitted pollution, in the process. And then there's the repairs and replacement parts. I don't know what the answer is. I DO know, however, that we cannot use "efficiency" to get us out of "trouble" as "efficiency" always leads to increased overall consumption: see Jevons Paradox. We live on a finite planet. Perpetual growth (consumption) isn't possible.
I jumped in here at the last page. Didn't read from the start, did not read the article. I can state that I have no interest in driving anything other than my ALH-powered MKIVs: I've notched up a couple more 800+ mile tanks- I am pretty sure I could hit 900 miles if I got out on the highway and just drove as far as I could. My car is averaging 51.2 mpg over the span of 87k miles (since I've owned it) and has never left me stranded (had a starter fail on me [I botched the rebuild on the starter- MY fault!], but my car's a manual so was able to compression start it). And on all such cars I've had (have had four at one time, now only two) there's never been a stranding (well, wife had a flat tire- I think she drove off from home with it that way!).