user-1: I'd like to propose to undelete this answer as I think it's a reasonable, on-topic, answer.
The reason being that there are many teachers that teach meditation without having goals, that having these goals (or "speedy progress") are actually harmful. Even in the context of samadhi itself, some teachers suggest abandoning the desires of attaining samadhi, as these become an obstacle to the actual attainment.

user-1: Thank you for the post.
I have undeleted the answer as I think you both make some valid points.
Although I still think that the question(s) should be addressed. The answer does not attempt to answer them.

How effectively fast is it? How is Metta properly cultivated as a meditation? As in how to develop the Vitakka Vicara on metta in meditation?

Its best that the Community decide about the post. I want to also mention that I think the answerer had wholesome intentions when posting the answer/advice regarding progressing too fast.
I myself fully agree that wanting to progress fast in the practice can be one of the greatest obstacles to progress. I did not mention it in my post as OP didn't ask about it though.
With Metta.

-1: <p>I'd like to propose to undelete <a href="https://buddhism.stackexchange.com/a/21014/382">this answer</a> as I think it's a reasonable, on-topic, answer.</p>

<p>The reason being that there are many teachers that teach meditation without having goals, that having these goals (or "speedy progress") are actually harmful. Even in the context of samadhi itself, some teachers suggest abandoning the desires of attaining samadhi, as these become an obstacle to the actual attainment.</p>
 -1: <p>Thank you for the post.
I have undeleted the answer as I think you both make some valid points.</p>

<p>Although I still think that the question(s) should be addressed. The answer does not attempt to answer them.</p>

<blockquote>
  <p><em>How effectively fast is it? How is Metta properly cultivated as a meditation? As in how to develop the Vitakka Vicara on metta in meditation?</em></p>
</blockquote>

<p>Its best that the Community decide about the post. I want to also mention that I think the answerer had wholesome intentions when posting the answer/advice regarding progressing too fast.</p>

<p>I myself fully agree that wanting to progress fast in the practice can be one of the greatest obstacles to progress. I did not mention it in my post as OP didn't ask about it though.</p>

<p>With Metta.</p>
