How do we, and more importantly how do adventurous end users, distinguish useful from useless from harmful configuration changes? Why should I trust this person

How do we, and more importantly how do adventurous end users, distinguish useful from useless from harmful configuration changes? Why should I trust this person? Why should I think it's worth my time? I find that these accumulated lists of security ideas are usually dangerous - in any domain, not just Firefox or browsers. They collect information and misinformation and add a veneer of legitimacy. Some settings don't behave as you think; some aren't documented; some are poorly implemented or tested by the vendor, who didn't design them for end users, and their malfunctions can create more security holes. Some are implemented for reasons you don't understand ('before you tear down a fence, know the reason it was put there'). Some are dependencies for other settings, features, and subsystems. It would have to be work by an expert in browsers or Firefox or security, such as a Mozilla engineer or someone like Giorgio Maone, for me to trust a list like this one.