@phatron- keep on tuning brother. I feel the same way about afr tuning unless your just after every ounce of power. Even trying to use afr to speed up flame propogation is rather pointless. As for egt, I've always looked at having two types of high egt. One from leaner afr and one from retard timing with the latter not being of much harm to the engine.
With regards to the fueling table, those are not target values. Those values are only enrichment or enleanment of the base fuel curve set by the maf scale. They could have scaled the injectors and maf to different values and made the table more accurate to actual afr values. I think they could have accomplished the same goal by making the maf scale a 3d table.
I think a whole different team of engineers tuned the jdm cars from the rest as most of the jdm tunes look to use a different strategy than say the usdm tunes. Even though the fuel is a better octane in japan, you can just tell that a lot of the tunes were done with a different mindset.