Although something may appear to work ‘in theory’, this alone doesn’t mean it will actually be effective in practice.
Although an explanation of how or why a treatment works may appear logical or convincing, this is not proof of efficacy. Rigorous testing is required to properly evidence the efficacy and safety of a treatment.
For example, castration has sometimes been advocated as a solution to aggressive male dogs. The rationale is often that testosterone, which has been linked to aggressive behaviours, is primarily produced in the testes and so removal of these organs will reduce aggressive behaviours. This rationale is logical and draws on previous research on the correlations between testosterone and aggressive behaviour. In practice, however, we have seen that castration is often ineffective in changing the behaviour of aggressive dogs. It does not work as well in practice as theory suggests.
BEWARE if a claim about the effects of a treatment is based only on an explanation of how it works.
REMEMBER: Treatments that should work in theory do not always work in practice.