Good MPG is 95% about where you live, and only 5% about carefull driving, most of the Mickey-mouse driving techniques that appear to be - being used in the US to save cash would get you banned from driving in the UK.
I would not advocate increasing tyre pressures to save money, safety is far more important in my opinion. And in some areas, lower than recommended tyre pressures are safer..
Neither would I put my car into neutral when travelling.. I consider that dangerous, both for me and for those traveling around me.. I'd hate to think what might happen on older cars who vacuum systems leak (and thousands must) to varying degrees.. oops no brakes!! duhhh..
But overall, petrol engines are gas guzzlers.. That's a fact.. In the US you only have very limited access to anything else really, so you have a very slanted view of what is, and what isn't, good mpg for a saloon car.. At an overall ave of 44 mpg ish my ZX is in the "ok" range, but there are dozens of manuals available in the EU and UK that can beat it out of sight!
As a Brit reading this site, the constant discussions and pre-occupation with trying to improve the mpg of a petrol engined Honda Accord is quite funny really, if mpg matters to people here they just don't buy that type of car..
If people in the US really want to improve mpg on their personal transport, then they should get your gov to lift import tax on diesel cars. And untill such time as that happens, your ave mpg is, and will continue to be, just a bad joke. ..