Most of the battery saving applications are better termed as "settings managers", if you already know how to turn things on & off there isn't much they can do for you. Plus it is another application now running.
Newer phones also have employed better hardware , better techniques and more power savings into the whole system, improving that before installing these. The newer phones are also going to sleep/standby using less power than they did before, still staying radio connected to the towers. Plus the phones have thier own settings for user adjustable power savings, like WiFi off when screen off , and data control.
Larger screens taking more power, plus major cpu sleepy modes, means there are times when a automatic backlight control could save more than (something like) turning off bluetooth. Again all depending on how you use it.
The displayed percentages of a battery and its voltages are not a great indicator of a specific ammount of power used, Or capacity left. Depending on the method employed to provide the battery level vision to the user. Testing for a whole battery cycle even might not determine a small ammount of savings achieved. High power use can drop the voltage seen quick, and other factors that do not represent the actual capacity left, or the moment it will no longer be able to make a call.
So in conclusion the usual battery management applications would be more useful for the unaware, and uncontrolled use of a phone, the automation that can save some power, most of it the same control that a user in controll can do manually. The phones themselves being much better at it , than when the origins of this type of application would have shown more differances.
You would also have to test for days, not hours, somehow doing everything exactally the same as before, which includes odd things like distance to the tower, which is more power employed to connect to it.
