Just finished an 11 week ckd. Great fat loss! Down to 10%
bf easy.
As for caffeine, It never kicked me out of keto, or had negative effects during the diet. You'll get max fat loss if you can drink 1-2 gallons of water a day on the diet though. It's hard to do that if you're drinking coffee all day also. I usually had coffee all morning, then after the 1 or 2 cups I had after arriving at work, I switched to all water. But I also took an "ECA" type stack too that morning.