It's an interesting exercise in déja vu as ten years ago I lost 8 st 2 lbs over about ten months (and kept it off for almost five years!). That was in the olden days when I used WeightWatchers' 123-Success-2000 CD-Rom which involved turning on the computer in the Study, firing up the program, putting the CD in, searching for the items... the App on my iPhone in my pocket with the barcode scanner, and the thousands of people adding all the foods to MFP, makes everything SO much easier!
I can conclude that food diary tracking definitely works for me in reducing the ridiculous amount of snacks and treats I eat if I'm not paying attention. The effect does wear off eventually, though, when I hit maintenance weight, so I need to have a think about how to deal with this when the time comes.