Hey, man. I've posted a few times on this. My most successful cycle ever in terms of physique transformation was Primo/D-bol while on a ketogenic diet. I absolutely loved it. I got great strength gains while really leaning up nicely. I probably put on 3-5 lbs of muscle while losing 7-10 lbs of fat. Plus, I kept my strength gains when I came off. I will definitely do it again when the time is right.
Here is a pic of me from at the end of that cycle:
serge, that is true. but he didn't ask about gaining mass. he asked about losing fat while still getting enough calories to make the cycle effective. this, you certainly can do.