You do know what "unique" means in this context, right? Hint: it means that antidepressants are the exception to my argument because psychopharmacology is so much more dependent on genetic/environmental factors than the rest of the pharmacological field that we cannot draw conclusions on the effectiveness of dosages pre-treatment without spending 100-1000x more time and money on the clinical trials than we do now.

Please take your clearly ignorant bias and anti-pharma prejudice somewhere else - you have no idea what you're talking about.

It is not a guess. It is statistics. Typically, the dose is either effective or partially effective and often on the smaller side as Phase 3 also looks at side effects.