Could an alliance of third parties be the way to push proportional representation, etc.?

It’s been there forever.

You did a great deal more than toss out a link to FairVote, but you said early on, ‘If you don’t like this, join FairVote and support proportional representation’ (I am paraphrasing to the smallest extent) and the whole thing is an argument about why proportional representation is a good idea, which refers back to ‘join FairVote.’ It’s a worthwhile thread topic but I wasn’t comfortable with such a blatant appeal to join a campaign.

Sure.