Hmm, let's define effective: "producing a decided, decisive, or desired effect" (Merriam-Webster).
Once again slogans and jargon are taking the place of thought. Left out of the discussion is what constitutes or is the defining characteristic of "effective teaching." I'll take my cue from Walker Percy's Lost in the Cosmos here and see if I can shed light on the question by posing several possibilities of what the effective teacher is or does.
(a) The effective teacher is one who connects with all of his students and helps each one of them to explore the mystery of the universe in unique and unexpected ways. This teacher is like Socrates, Jesus and Buddha all rolled into one, except he does not alienate anyone. He is able to impart wisdom simply by his presence. All of his students are above average and getting better and better, every day and in every way.
(b) The effective teacher improves all students' performance on standardized tests and clearly the students learn other great things as well. He's loved by all.
Question: Did you notice the farcical quality of options A & B? If not, you are probably a political commentator, politician, or a member of a non-profit organization that concerns itself with education reform. It is unlikely you have children of your own or that you are a teacher or spend much time on this planet.
(c) The effective teacher figures out how he will be evaluated and maximizes his efforts in these areas. If effectiveness is measured by standardized tests, the teacher focuses on techniques and imparting knowledge of these things. If, on the other hand, his evaluation depends on something else, something else is what the teacher delivers. This teacher is like a mirror for what is asked of him by the dominant power. He is truly self-less.
(d) The effective teacher cares not a whit about the latest fad in education or his own fate because of his disinterest in said fad. This teacher is really good at communicating some very important things to some students, helping many students some of the time, confusing a few students not so often. In short, this teacher is very human.
(e) The effective teacher is a combination of C & D.
(f) The effective teacher is undefinable and unclassifiable. First because we don't know (or agree) on what we want concerning outcomes with students. Second, we don't know why some techniques "work" (have an effect on a group of students) while those same techniques in the hands of another teacher teaching another group of students fail miserably. In other words, teaching is more art than science, but, living as we do, in the age where technology seems capable of solving all of our problems, we're unwilling to admit that science and technology can't help us much here. We're back to Plato in the Meno where Socrates asks, "Can virtue be taught?" Like Meno, we want to reduce the question. Thus we spend enormous amounts of time, energy and money attempting to do what cannot be done: making education a purely rational (abstract) activity.