Agreed. Each person should do their own testing. Each person should do their own research. With that said, however:

I had this "tire pressure" discussion with the World's Greatest Hypermiler (we all know him) and he convinced me personally (after I had similar concerns about safety/grip/wear etc) that higher tire pressures are safe and that they do not increase untoward tire wear and that they DO help MPG.

I ran my 2004 HCH for about 20,000 miles with PSI about 20 higher than recommended. The car rode and handled fine, and the tires wore normally. I'm running my TCH at 46-50, and I might go higher.

I have the advantage of living in DRY Phoenix and grip in the rain is not an issue. My driving style does not lend itself to the tires losing grip under any circumstances.

On Synthetic oil, well, there is really no solid, undeniable, scientific evidence that it helps your MPG. What it DOES DO, without a scientific doubt, is protect your engine better than Dino oil. So if you want to protect your engine in the best (not cheapest) way, synthetic oil is better. Not necessarily for increased MPG, though. Synthetic oil in my 2004 HCH made ZERO difference at all in MPG, and I checked it carefully.

To each their own, and Your Mileage May Vary (but at least you can hope it varies UPWARD !!!)

Lars