Very comprehensive. Thanks! But yes, you did forget something. I live in France and it doesn't make any sense for me to fly to London, Madrid, Rome, etc, on LH beacuse I would have to connect through FRA or MUC. Miles are important, but getting to my destination on time is more important. When you have two legs to your destination, you are doubling the risk of delays. Most all of my Euro flights are on AF. This is why I am Platinum with AF. Plus AF gives double miles for all flights, and any bonus you might earn for biz or some promo.
So my Star Alliance trips are the long hauls, especially the RTW's as Skyteam is not a good alliance for RTW's. So let's break down RTW's for this purpose.
So lets narrow this down a bit. Say I do 120K miles per year just on RTW's and they are all in biz. Each RTW includes both a leg in and out of the US. Say I don't care about UA system wide upgrades since I'm comfortable in biz and don't really need F. Should I book those 120K miles with M&M or UA?