>No it doesn't.
No one denies that the explosions are an act of sabotage. How do you imagine non-deliberate explosions happening approximately at the same time and of such power as to cause seismic sensors to reliably detect them?
https://www.youtube.com/watch?v=2TgSGylIw2A
That in turn were quoting usual explanations from the Blue Book Project era.
I believe this is sabotage. I have no idea who did it and why, but saying "Hey, there are two ships, miles away from the site with transponders off. It's them!" is a bit of a stretch.
With all the rhetoric from the US about not allowing NS2 using any means, I think that it's quite possible that charges were planted long before the explosions and were activated remotely.
Then you completely misread the comment you originally responded to, and this entire thread is a waste of time. All they said was that the dark ship evidence does not prove sabotage. And you say the same thing, that the dark ship may or may not be responsible.
Maybe they didn't expect to get caught. It seems we're assisting to a recalibration of what's possible in several fields.
At a wild guess, there'd be multiple merchant vessels travelling past the point where the pipes were attacked. Who would notice if a group of divers happened to leave a ship as it transited?
And of course, those vessels could be flagged under many a convenient jurisdiction. Liberia used to have the world's largest merchant marine, theoretically.
Whereas if you go in with a submarine, and it gets detected in the vicinity, it's far harder to plausibly deny that your country wasn't involved.
TL;DR - you're assuming a submarine would be stealthier, but there's a lot of stealth to be had from hiding in the crowd.
I think the obvious conclusion is a false flag operation, but again, all evidence is circumstantial.