I do MMA, and my gym has a Muay Thai class taught on the other side of the mats which I was considering joining also. The other day I was observing it and the instructor was teaching the students something called "the heavy jab," a modification on a normal jab in which the shoulder was pulled back first and then surged forward with the arm to create an extra-forceful jab.
Confession: I have little knowledge or experience of muay thai.
Suspicion: The heavy jab is bullshit.
I couldn't find any reference to it on the internet, not a single mention, and it just didn't look right. It looked ridiculous and ineffective, telegraphing horribly as the shoulder pulled back in preparation to strike.
Am I incorrect? Is this a thing? Is there a definite benefit to this technique?