agreed it's a silly question especially if someone reading it has the goal of becoming the 'complete MAist'... but I disagree that it's 'wrong'.
everyone has their own goals for training (or not training for that matter). If the goal is to be able to hit harder, then concentrating on technique(s) towards that end is not wrong.
if someone has a balance issue for instance, concentrating on improving that exclusively for a period of time may be the step towards a longer term training goal.
Is it more 'correct' to maintain a uniform curriculum vs diving deep in a much smaller set of techniques that are tailored for personal goals?
Martial arts and techniques are not ''seperate'' they are ''connected''
Per example... Your balance affects everything. As does your flexibility.
From there on it's muscle mass & speed
And from there on it gets down to the differences in techniques you may focus your training on kicks for awhile improving your balance and midsection strength and then going back to punches you might discover your physical ability there has improved as well.
But as to the question itself my answer simply is ''my favorite technique'' simply because it would have to be something I enjoy practicing and have a ''talent for''