> If a year didn't work, how would you know that 2 years want going to work? or 5 years?
The time frame is not relevant as people differ in their abilities, as you have noted. Typically there would be some measurable change that helps determine how "you" are feeling overall in the process, not how other people felt at the indicated time frame. After all the goal is for "you" to feel better, which is subjective to everyone.
> The problem isn't that you have to try it to see if it's works.
I'm not sure I see how this would work any other way than trying it. A person is only trying the recommendation not perfecting it.
> The problem is that psych professionals a) have a poor grasp of decision theory and b) have an incentive to optimise their time and not the patients.
I'm not directly following how this relates to the original comment stating that recommending something for someone was toxic. Much like all professions some people are better at their job than others, sometimes you find the right fit, sometimes you have to keep going. We all have to walk our own path, no one can walk it for us.
*"you" is in the objective sense, not directed at you specifically.