Fat gram intake is actually the only thing I do when I'm dieting (which I'm currently not
). I lost 96 lbs in 10 month on low fat dieting and exercising alone. I don't count calories or carbs. I originally ate 30 grams of fat per day, eventually cutting it back to 20 on the 2 days I didn't work out and 25 on the 5 days per week I did. It certainly isn't the thing for everyone but for me, who is way more of a fat food addict than a carb addict, it does the trick.
I agree with most those that just plain sensible portions and sensible choices are the best way to go. For me I needed some kind of guidelines and knew eating too much fat was my problem so I chose to make that the # I count. I have figured out a few times approximately what my caloric intake is and it runs around 1500 on the average day when I'm dieting.
Just thought I'd throw my two cents worth in!