All the studies that I've read about weight-loss and ratios of carbs protein and fat indicate that people tend to initially lose weight faster on high protein diets but that in the end all diets are equally successful. The bad thing about high fat foods is that you must eat a smaller amount since fat is more calorie-dense.
However, I think it tends to be personal. Some people need that protein to be full. Some need a little more fat content to stay full. Personally, I stay full longer with high fiber foods and foods that need to be chewed more. But everyone needs a little fat in their diet because it's essential for life... preferably canola or olive oil fat sources... or fish.
In general, it may be wise for people who are over 50 years old if they have heart/stroke concerns to start watching their fat intake and try to stick to less than 30% calories from fat. Less than 30% calories from fat is recommended for people who have high cholestrol or lipid levels.