what worked best? kissing off [most] carbs.
I found CICO by itself to be utterly useless, if also technically & trivially true. I didn't overeat because I wanted to; I overate because the things I ate made me inappropriately hungry through their endocrine effects. After many failed attempts to "just eat less" I realized that trying to make a life change contrary to instinct is a recipe for failure. You have to change the instinct, not just hope to ignore it. Willpower is a limited resource.
Happily, as soon as I quit eating the bulk grains and sugars that our Western diet so blithely embraces, and began eating just about everything we are routinely told to avoid (red meat, saturated fat, eggs, butter), the appetite aligned itself with my energy needs (as it does in nearly all other animals, except domesticated ones fed on grains) and the weight just melted off. A laundry list of health problems and ominous lab results vanished with it. Nearing two years in, I'm down to 215 from 340, and I'm not done yet.
I got here eating things I love (steaks, seafood, rich salads, nuts) and at ~2800 cal/day I never had to starve myself either. For exercise, I just walk, & sprint every now & then. Sure, I miss bread and pasta, but giving them up is way easier than subjecting myself to tasteless shake mixes and "low fat"/"nonfat" imitation food, gasping my lungs out on treadmills and stationary bikes, and feeling perpetually ravenous for my next wheat/glucose fix. THAT is what's truly "unsustainable" (a word that is continually misapplied to LC/Paleo plans, mainly by people who haven't tried them)