This is a major point, that the Sony Engineer had a reason for not grounding the 4.4mm
Unfortunately, nothing is that simple.
- Why did they choose to use OFC wiring for the 4.4mm jacks on the WM1A, and Kimber on the WM1Z? Was that the best? But there are many mods that people have said is a major improvement. The K mod from Singapore, mods by
@Nayparm,
@Whitigir, Romi, etc.
- Why did they put in relays in the signal path to the 4.4mm. Yes, it blocks transient noise from signal switch/turn on, etc. But this is cosmetic, and not necessary overall. This causes a major deterioration of the signal integrity, due to the weak/small relay contacts. This extra circuitry is, to me, massively detrimental to the signal.
Why, oh Why did the Sony Engineers put this cosmetic design/weakness in, is what I have asked, many times.
So to say that a Sony Engineer will make perfect decisions, ALWAYs, is not true. Sony engineers have massively more knowledge and experience than the average user. But they also have weaknesses and blind spots, like anybody else. Less than most, but there are still areas that they also are weak in their knowledge. They are, after all, only human.
And I also would give my trust to the Sony Engineer's knowledge and experience. But I would not impute on them the expectation to be perfect and infallible. Nobody is, and knowledge can always be expanded on, modified, changed.
And to use the reasoning that "X company's engineer made the design decision, so it must be the best design", cannot be a blanket rationale, as all engineers have constraints and goals imposed on them, along with their personal bias from their training, experience, background. Else why would successive products have improvements? Because those self same engineers grew their knowledge and experience, and found better ways to do things. Or had less or different constraints imposed on them.
Knowledge is not finite, but just a base to expand upon.
So the current situation is normal. Each person evaluates, and makes their choice, for their own system (equipment, music, ears). There is no one size fits all solution, and never will be.