There actually are shorter-form therapies derived from psychoanalysis that do have manuals, and studies purporting to show their effectiveness. The point wasn't that these therapies are all that great - they probably aren't - but that measuring psychotherapy is a methodological ball of tar and prone to confirmation bias.
Most therapists highly individualize their approach - just because they have the same name doesn't mean they're actually doing anything similar. So claims of "empirical" proof of psychoanalysis is nonsense. The nature of what psychoanalysis is precludes that.