Since I'm still eating that lean beef, I have also been eating tallow. It's funny, the main mod of /r/zerocarb always describes the limit on fat intake as nausea but I find I know I've had enough well before the nausea limit hits. I reckon that makes sense too - as a fat eating animal, we must get an idea of full before any ill effects kick in.

Even the carbs turning off the ability to tell when you've had enough makes sense when you consider how available carbs were when humans evolved far from the tropical forests where our ape forebears live eating fruit all day - it made sense for pre-agriculture humans to gorge on fruit during the month or so it was available, and put on fat for winter.