I know that this piece was some kind of spoof.
No it is not actually. A lot of people react in this way to what we write. We leave it as an exercise for other Members to work out why that should be.
An intereting retort, to be sure - and one which perhaps reveals your achievement as even greater than i had previously though, since you so effectively made it sound like one...
. . . this monumental symphony was written in just three weeks . . .
If we may say so that does not surprise us. Indeed it is eminently credible. But does it help the music? It is is it not always better to take one's time when writing music? Bach and Mozart wrote very quickly, but Bach kept on tinkering with his movements for years afterwards, improving them in many ways. Mozart was an unique genius and S. was no Mozart.
And your point is...? Shostakovich spent a lot longer on his Tenth Symphony, a work of approximately the same overall dimensions and I mentioned the astonishing speed at which he wrote his Eighth merely to illustrate - as surely everyone else accepts - that he was capable of expressing such thoughts on such a scale within an almost alarmingly short space of time; there was never any question that this compositional velocity resulted from anything other than total and sincere devotion to the job in hand, for there is nothing slapdash about this symphony at all.
Many more recent composers such as Beethoven, Brahms, Tchaikoffski, Elgar and Sibelius spent years on their symphonies - too long even, in some cases, where their first drafts and thoughts might have been better after all.
So what? Only its composer will know how long it may take him/her to compose a symphony and the amount of time taken for each one will depend entirely on the composer and the symphony concerned - as indeed should be the case, although the fact that it took Elgar (whom you mention here) well over sixty years to complete his Third Symphony is rather unusual in more respects than one. To be more serious, however, one could consider the example of Comrade Medtner, who took some 45 years to complete his Piano Quintet (a nevertheless rather disappointing work, by his own best standards, "we" think).
Erwartung on the other hand was dashed off in a kind of trance state. We don't think S. was in a state of trance.
One would surely have to be something beyond the mere genius that Comrade Schönberg was in order to conceive and write down a work as powerful and detailed as
Erwartung in any state other than full consciousness.
But in general is not polish the great indispensability in all Art?
Did anyone here suggest otherwise?
In this Eighth Symphony polish appears more a desideratum. Which perhaps brings us back to something Member Time Is Now was saying.
Er - no; all that it actually "brings us back to" is a sense of despair at your astonishing ineptitude and utter lack of perception and sensitivity towards this work, whose greatness one would at least have expected to elicit due appreciation from your critical faculties even if the work itself does not necessarily appeal to you personally...
Best,
Alistair