I've done IF in various forms, including a long stint (3-4 months) of Leangains. No effect. Right now I fast Saturday mornings because I don't work out Saturdays and usually don't get hungry until the afternoon. I like fasting, and I think it probably has other non-fat-loss benefits, but it does nothing to help me lost fat.
Anytime I try a tweak, I give it at least three weeks before deciding it's not doing anything. I've calorie restricted down to 1000/day and all it Reid was make me feel tired and starving, and my workouts sucked. Body comp remained unchanged.
The only times in my entire life that I've visibly or measurably lost fat was when I was working out hardcore. As I am now. And like I said, I don't mind working out hardcore. I just want to know why food has no effect on things. And when I say food has no effect on things, it goes both ways--based on past experience, I could eat a cheat meal every single day and it'd also have no effect. I don't know what would happen if I gorged on SAD food constantly, though. And let's just say it's doubtful that I'd ever do that experiment.
To those saying "it's hard to lose those last few vanity pounds"--this is not that. I sit between 28 and 30% body fat, and could visibly stand to lose 20 pounds, even 30 if I wanted to be called "lean". And I've never been heavier than this, either. I have literally been at this weight and body comp for a decade with no ability to change it.