I take it you don't know any bodybuilders, or any guys in a weight-class sport, like wrestling, boxing, BJJ or MMA.
I think exercise can be feedback unto itself. Performance gains in strength training and calisthenics come surprisingly fast.
This article is obviously not targeted at body builders.
Literally counting every calorie gets old quick, but I think everyone should be able to estimate their calorie intake. It doesn't take long to calibrate your own intuition; after a week of paying close attention, most people should be able to guess the calorie contents of a plate of food.
Sadly, a general resolution to "watch your calories" just doesn't do it.
In order to work, a weight-loss system has to remind you each day of where you're at (in perspective with where you've come from). Ultimately there's only two measurements that count: your weight and your body fat percentage. Measure those every day and you'll be much further on the way to weight loss than by calorie counting. Sure, being aware of your rough calorie intake is useful supporting data, but you need to measure the end result to get the "proper" feedback.
The end result of weight loss is not calorie intake, it's loss of weight. If you want to achieve that end result, you need to measure it. Sounds simple enough, no?
Also, the end result is fat loss, not weight. Which is why I think weight is not the best metric, but performance in physical tasks. (As most people can't get their bodyfat percentage checked regularly, and performing various physical tasks is what allows you to keep or increase muscle mass while losing body fat.)
As I propose in my article here: http://www.inter-sections.net/2008/01/02/feedback/ - you need a good, timely, but also effortless system of feedback. Something that requires you to carry a notepad and add up numbers every day is a still-born failure.
The system that worked extremely well for me was much simpler: weigh yourself every day (including body fat %). Plot that on a grid, and that'll provide you motivation enough to keep your calorie intake down.
As an engineer, you should be aware that there's a few key vital behaviours that, if you implement them, typically make all the difference. According to various food associations, there's 3 vital behaviours for losing weight:
- Weigh yourself every day
- Eat breakfast every day
- Have a way to exercise at home
Since I lost 10kg in 3 months by doing just 2 out of those 3 (but going heavy on the "weigh yourself" bit by actually charting my weight and BF%), I can say that it certainly seemed to work for me.