[ChrisKor]

I have heard that Twitter is working on something like this. The hard part of course being the detection of what is an argument and what is commentary or anecdote sharing.

>As an aside, I wonder how good grammar checkers have become since the Word 97 days? My grammar is utterly terrible and I wish I could get it proofread before I make comments.

Try it for free, Google Docs added it recently for English. Otherwise, perhaps one of these dedicated sites or use their browser extensions, will be of interest:

https://languagetool.org/ https://grammarly.com/ https://www.gingersoftware.com/grammarcheck