[mannykannot]

Is sound engineering judgement a technical skill or a soft skill? How about the ability to articulate that judgement, so as to explain to others that one set of choices is better than the alternatives, and persuade them to agree?

[zunger]

Yes. :)

Sound engineering judgment typically implies a good understanding of the full context of the problem ("is this a good tradeoff?"), which often involves things beyond the merely technical. And without all of the other things you mention, which are definitely in the category normally called "soft skills," the best engineering judgment in the world will go to waste.