On the Process of Interpretation in Music - Two Words with the same meaning?

For me, the word 'opinion' is simply another word for 'interpretation,' when the issue of the ways of dealing with the core meaning of a composition is addressed. To enter into an attempt to explain:
It seems, in general conversation, that more times than once I encounter the impression on the part of some that continues to persist when the name Toscanini is raised.
There continues to exist a premise that the universally known tyranny of the legendary conductor was the result of his insistence that the interpretation of a composer must come to rest in totality upon the composer's  own view of  that piece. And, on the surface it seemingly makes sense as to the magnificent intransigence of Arturo Toscanini, in what is known about the countless examples of  those fearful fits of temper he flung out to the unfortunates who dared to veer off the road during rehearsals.
But, in listening to recordings of the same composition by Toscanini (which are available), one will note a difference of opinion by Toscanini himself as he travels from one period in his lengthy career to another.
First of all, how many of us  were THERE at the creation of a Beethoven symphony or a Mozart concerto? How is it possible to know what were precisely the whims of the composer in his view of that masterpiece, and at that time? And; secondly,  the composer himself may well  alter his views about a given creation as a normal  part of that process we call 'growth.'
I recall that telegram sent by the composer Prokofiev to the pianist Horowitz during the Second World War after hearing the great Russian virtuoso's performance of  one of the so-called "war" sonatas that Prokofiev had written: "my congratulations to the great pianist who found more in my music than I  did(had)."
Great art, in no matter what form, has no bottom, no top. One can only speculate as to the whim of the composer. The performances that to me are 'great' are those I recognize as those given us by the performer who has an  impressive level of   contact with the historical context, the genius of the writer, and the ability to project at a high level.
What comes to mind is what the Spanish violinist Ricardo Odriozola projects in his liner notes in a Bach album he released not too long ago - without a trace of ego, Odriozola  discusses his contact with the composer as being of relevance and import, in describing his contribution to the recorded works of the Baroque legend. Do listen, and see  if you agree with my opinion that there is much said.
What, in your opinion, does the word 'great' mean to you, as you listen to the music of your choice?

The Idefinable Ubiquity of Music...

As I may have mentioned before;  for me, the two most ubiquitous bedfellows in Human History are War  and Music. The dominating question I sometimes ask myself;  which came first?  Do read on:
That unique moment in World War I, when a number of opposing troops stopped killing one another in order to sing Christmas carols together, essentially stopping Time - followed by the resumption of the killing.
Or, the German pop tune, Lili Marlene - there were times when that tune was sung by both sides during that war, in German and English. There were moments when the opposing troops could hear the song in both languages simultaneously during quieter times - how about THAT as an example of the station of popularity?
Between the two great wars, in the early thirties, two nations were involved at the same time in massive re-development; one, led by a new president named Roosevelt in a program designed to  bring a culture back from the shattering calamity called the Depression; the other, led by a man named Hitler, in order to prepare for ultimate world domination(proven in Hitler's Second Book). A pop tune, written in, I believe, 1929, titled "Happy Days Are Here Again" was sung in both countries during this period, again in English and German.
During the Battle for Britain in World War II, when English airmen began bombing cities in Germany, that 18th century Scottish tune, "My Bonnie Lies Over the Ocean" appeared with new lyrics sung by the British pilots - instead of "bring back, bring back, bring back my Bonnie to me" the words were "bring back, bring back, bring back my bomber AND me."
Music - always there; just  waiting...

The Stamp of Genius In the World of Music, As Given Us In The Product...

Traditionally, when we ruminate on  the impact of genius as it appears in the arts, the core of thought  quite  often centers around the impact of the attainment levels of the artist being discussed; for example, it has been said that Mozart began writing music before he could write his name;  or,
Liszt began the development of his pyro-technique at the piano by the age of eleven or twelve;  or,
Gershwin alters the direction of history with his Rhapsody in Blue; and, so on...
I thought that it might be fun to mull over specific products  left by the genius being discussed, if for no reason other than to, perhaps, grasp a more lucid example of the significance of that attainment:
How about a chap named Pergolesi? This 18th century composer established, once and for all, comic opera, and became firmly established as a force in lyric opera, having created a language of his own, and,sadly, for such a tiny particle of Time. He passed away at age 26 - how many know of him today?
Let's consider the Brontes - we, of course,  know much about this family. "Jane Eyre" and "Wuthering Heights" come to mind, among other great novels written by members of the Bronte family.
Anne Bronte dies at age 29; Emily, at age 30. Such a tiny particle of Time...
What about John Keats, one of the great lyricists of his time? His poetry remains, for us, some of the most beautiful coming out of English Romanticism. He is taken from us at age 25...
Arguably the most powerful conductor of the twentieth century, with an orchestra; namely,  the fabled NBC Symphony Orchestra, created just for him. The level of his demands remains the source of conversation to this day. Arturo Toscanini remained tight-lipped about talents of his contemporaries; however, when Guido Cantelli entered his life, Toscanini spoke more highly about the brilliant promise of this young conductor, and took him under his wing. It is generally thought that only Cantelli could become the official Toscanini Successor.
But Cantelli died in a plane crash near Paris  at age  36 - Toscanini was never told about the tragedy...
Vincent Van Gogh - the world knows his name, of course.
But, to further gain an understanding of the level of genius given to a human, why not take a look at the juvenilia by this artist, at, from ages 10 through 17?   As  a lost young soul, beset by his desire to become an active force in religion and/or human welfare, he  was always painting. Do search for and look at what this kid could do before age twenty...
Jascha Heifetz is also well-known for his days as a child prodigy. For me, perhaps the most significant product he left  was   his performing the Mendelssohn Violin Concerto at what  was, I think, his debut performance - at age  9...
Alexander Scriabin left his stamp when he moved from late Romanticism to Mysticism, all within forty-odd years. And his son, Julian, left four little preludes. For those of you who can detect stylistic differentiation in  music writing, but are not familiar with these pieces, take a look at them; then ask, how can a child of eleven  write music like this? It's almost as if Julian took up where his father left off- nothing like this is replicated in the history of the art.
And Julian died that year, at age 11, in a drowning accident...