Wow, this went all over I think CICO can be important, I think that if I ate that many calories (and I realized later that wasn't even it, I forgot a side dish of veggies and butter) every day for a long time and really didn't do any exercise that I would most definitely gain weight, regardless of how clean I was eating, even if I took out the dairy and was getting all those calories through coconut oil, etc. I also think CICO on a day to day basis isn't that important, I try to look at weekly averages over day to day numbers anyway. My weekly average won't be nearly that high as I usually have at least a couple really busy days where I work and have to do other things and am lucky to get in 1200-1500 calories that day, so I usually average around 1500-1800 most of the time I would say.
I also think paleotrack might have some issues, I didn't do it yet, but I think I might enter the stuff into myfitnesspal to see what it says. I actually didn't even feel like I overate at all, I was actually quite surprised to see numbers that high. I figured that it was the drinkable calories though (bulletproof coffee, etc.) that drove it up so high even though I didn't feel like I overate. Now, I ate GOOD, I full and warmly satisfied at the end of the day, but I didn't feel out of sorts. I have two meals (lunch+dinner) and the coffee stuff was in the morning. Lunch was baked seasoned salmon (abt 7 or 8 oz) with a small bowl of salad (evoo+vinegar), some sweet peas with butter, and a bowl of mixed fruit (mango/banana/blueberries) and dinner was probably about 3/4 lb of baked seasoned chicken (with skin), 1/2 small eggplant w/ evoo (roasted), about 8 asparagus spears (in butter), and two small pears baked in a butter sauce. Other than that stuff just butter and whipping cream in coffee.
I have also read a lot of things about women not being able to get quite as free with the fat and seeing similar (lean) results, and I can imagine that could be the case for a lot of women, myself included. I lost a lot more weight back when I did Atkins and fat was ok but I wasn't gulping it down by the cup. I'm pretty sure the fact that women can have babies and men can't might have something to do with this, it makes sense to me that a woman's body wouldn't lean out as much eating this way because women's bodies are supposed to be prepared to house another life and holding on to some extra fluff is probably beneficial for that.
I have found as time has gone on that it's not worth worrying about a day of way overeating. Like the time I ate and entire half a duck. I woke up the next morning, after tossing and turning and burning up with horrendous night sweats, so NOT hungry I skipped breakfast and went for a hike up a mountain. I skipped lunch, too. I felt amazing, like the half a duck actually did something good to me. Lately, I've been way overeating almost every day. Oddly there has been no weight gain at all. Instead, I've had more energy for my workouts and started riding my bike to work. Not as punishment but because I just feel good and want to do it.
So my advice is don't worry so much. Get back on track the next day. In the end, it probably won't hurt at all. Daily overeating of candy, cookies, pie and chips will hurt, but overeating on paleo food won't hurt once in a while. It'll probably do you good.
Female, 5'3", 50, Max squat: 202.5lbs. Max deadlift: 225 x 3.