"not every single thing that can be put in a ratio has empirical significance"
You may think I am bringing your attention to an obvious point. I am quite sure Gene agrees with you it's a relatively obvious point. Apparently it is one that does need to be belabored, and Gene is doing a valiant job at that.
To be fair, for me this obvious point was buried under a lot of other equations and sentences and ideas rendering it not immediately obvious (to me at least), so in that sense this is most definitely a public service.
Please click through - there's more than just this in there, including why the multiplier is a pro-market idea (I think we Keynesians forget that a lot of people have this odd idea that Keynesianism is not pro-market so we forget to highlight stuff like this because we don't usually think to juxtapose Keynesian ideas with pro-market ideas)