"The key mistake" Not really because I wrote it. I could have written 'glass recycling has the possibility to be sustainable', but instead I wrote 'glass recy

"The key mistake" Not really because I wrote it. I could have written 'glass recycling has the possibility to be sustainable', but instead I wrote 'glass recycling is sustainable assuming X' You could complain if I didn't state my assumptions, but I did. I currently buy 100% green electricity, I could use that to recycle glass today and that would be sustainable. So this isn't some hypothetical, it is possible today. That isn't to say that I disagree with your points though. It isn't an easy problem, and 'best' now, doesn't necessarily match 'best' in an ideal world.