"Superior" is a matter of preference. The word you were perhaps looking for is "different", which is a matter of fact.
I can see the reasoning behind that theory, but in practice the digital system gets it close enough for rock'n'roll. Remember that each sample represents a very small moment in time. Even at 16 bits, the error on any one sample is at or below the limits of audibility. If the input is silent, you might just hear a slight hiss from the dither under optimum conditions. As soon as you add other input, program or noise, masking effects make it impractical to hear the dither. Remember that the dither removes any program-related error due to finite quantisation and replaces it with uncorrelated noise.
Returning to the "superiority" of vinyl reproduction, I used to perform a party trick which gave many people food for thought. On their highly regarded turntable setup, I would play a simple 1 KHz tone from a test record. Then I would play the same tone from a test CD. The differences were not subtle. Then I would point out that the same problems audible in the LP playback of the tone were present in all music played on that turntable. If it couldn't get a single tone right, how could it hope to do justice to the music?

I did, and still do, derive a great deal of enjoyment from LP playback. And I'm not blind to the shortcomings of digital systems. But I know which I prefer, on balance.
One more point:
There is a widely held understanding that a "needledrop" of an LP, if done with care, sounds very much like the original LP playback. If the digital chain can do this accurately, it can likewise accurately capture / reproduce the original signal that was used to cut the LP. Any differences are therefore due to the LP cutting / reproduction chain and not to the digital chain. So if they sound different, which one is getting it wrong?
OK you lost me on this last point. I suspect some sort of editing problem? WRT your party trick, we do a similar thing with the 1KHz test tone at the studio, as a reference we will cut the 1KHz tone and then play it back on a Technics SL1200 with Grado Gold cartridge, through a 80s-style Japanese equalizer into our board. This is played against the test tone itself. Its hard to tell the difference!
'Superior' was in fact the word I was looking for. Mr. Wannamaker cites the need for listening as part of his thesis, and apparently for good reason. So I am going with that, although I do note that he did not in fact state the reason that listening comparisons were needed.
Well that doesn't make any sense. The stock Revox had been checked out. Its frequency response was up to snuff for such a machine. Not like all these spouting LP superiority have access to the original 15 ips safety copies to compare. Do we need pro level tape and machines to best CD? CD must be pretty awesome if we do. Nor do most people get the chance to compare more than what is available for consumers anyway.
I could supply much of the other info about the LP rigs though not all as it was awhile ago. The differences heard weren't of the type a cartridge tweak would or preamp swap would change. So would be a waste of time to bother with the rest of all the tiny details like which cabling was in use etc. The SOTA's were a Sapphire and Cosmos the Rega a Rega 3. The rest was as appropriate for the equipment.
Just for the record, a Rega arm does not allow proper setup of the cartridge. So in that case you were comparing an individual setup, not that actual media. I note that in your mention of the SOTA turntables, you are studious to avoid the mention of the arm or cartridge, and what means you used to determine loading (if any was needed; loading is a function of the phono preamp not the cartridge, if the cartridge is a low output moving coil).
Given the above I do feel that your comparisons had some shortcomings that led to a faulty conclusion; I am not contesting that you heard what you heard.
BTW if you really want to hear what tape can do, take the effort to locate a tape machine with better electronics. The Revox is a consumer grade machine and the electronics somewhat antiquated. If solid state I recommend a Studer (the pro version of a Revox, oddly enough sounds considerably better for some reason

- I'm going to guess that its because the Studer is not in fact junk) or get yourself a properly refurbished tube machine (we have Ampex 351s and even a 300 in the studio). I have master tapes and backup tapes (from EMI) of LPs that I have in my collection. In the case of the master tapes, they are recordings I made and I know exactly what they are supposed to sound like. FWIW, making and releasing your own recordings on LP and CD can be a real asset to understanding exactly how good your references are.
However this particular thread is really not supposed to be about LP vs CD so much as it was about the simple fact that more dynamic contrast con be heard on the LPs. In my case I find that about 90% of the LPs will have more bass impact than the CD, but there are a few that don't. One standout for me is the reissue of Voyage 34 by Porcupine Tree. I have the original press (which at one time was up to $1200 on eBay a few years ago). The reissue LP sounds compressed and dry. Apparently is was squeezed through ProTools at some point and it sounds like it: lifeless. The CD is much better, and so is the original LP (which is better than the CD).
One thing about the LP that is a variable, and is a thing that I don't see so much in CDs is that fact that later pressings of an LP generally don't sound so good. Being a bit of an audiophile, I do take the time to locate original pressings to avoid this problem. I can certainly see digital advocates not being as selective in this regard! And they would have a point too.
But the bottom line here, and something that will not change is the simple fact that the technology is taking a back seat to what the record labels do with the recordings. And in that regard, they will always be compressing digital recordings more than they will LPs, for no other reason than they expect the primary listening location to be in a car and they don't expect that with an LP.
This is as it always is, a marketing thing. We can and do argue until we are blue in the face, and none of that is going to change what the labels are up to.
So can we get along a bit better if we understand that the industry at large is really uninterested in audiophile goals, and won't be paying any more than lip service anytime soon? What this means is that we are talking about a very small bit of the pie, and no matter how good the LP is or how good the digital files are, for the most part their performance will not be realized.