If you are riding at high intensity (and your weekend rides certainly appear to qualify), you can't get the energy you need to sustain this effort from either fat or protein metabolism. Without food, muscle glycogen stores are fairly well depleted between 1 and 2 hours into the ride. At this point, I'd be worrying about bonking.
Controlling diet off the bike sounds like a better long-term strategy than reducing calorie intake when you really need it. It certainly worked better for me - I was where you were about a year ago, and am now where you want to be - I just had my body fat measured after XC ski racing all winter followed by 6 months of road riding and several triathlons, and it's now down to 10%.