Man... I struggle with the flash thing. I'm totally an ambient light/ISO/AP guy running after 3 kids on the move mostly. And if the ISO has to go fairly high, post edit in LR and done. Too dark? Then don't shoot. I HATE how flash treats most shots. Am I crazy?!
I think I need some good real world examples of flash done right (on camera) in very low light. And I don't mean the type of stuff that saves you a few hundred ISO, that is easily corrected in post.
Well if you limit it to "very low light", "on camera" and saving more than "a few hundred ISO" you're really restricting the use potential. Personally I don't like using flash as the SOLE light source either, but it can work wonders when diffused properly in mixed lighting situations for one thing. My primary use of flash is for outdoor fill. I can do a lot in post, yes, but really? Sit down at my computer, boot up Photoshop, grab the RAW, start playing with levels, and curves and blah, blah, blah... or... Take an extra two seconds to get the shot right, in-camera? Sure, post' has it's place but I like to
minimize the time I spend in post, personally, not take shots I know are going to require it just to pass muster. But, then, that's me and my style and my sense of workflow. If you just don't like flash, you're certainly not required to use it.