Sorry it didn't work out for you, hornet, but your conjectures about others getting good service are simply that, conjectures about how we do things.
When I first got my phone, I set it and let it alone, and got well over a day with plenty of use, background and syncing on, gps on - NO battery tweaks, not the "baby it" stuff you describe.
Night and day difference from my Evo.
And my battery claims don't involve underclocking at all.
Now, I will show respect for your personal experience but it's time for you to reciprocate.
Those of us getting the great service you didn't get are not wrong, inexperienced and not lacking in the ways of smartphone inner mysteries.
It's called your mileage may vary, that's all.