There's some interesting discussion of completion of symphonies in
today's Music & Vision magazine :

http://www.mvdaily.com/

'Another and most recent "completion" of Schubert's "Unfinished"
Symphony prompts me to wonder why this sort of aimless academic
exercise attracts so much attention - and investment, for these
completed works are performed, sometimes quite widely, by orchestras
that might more productively be devoting time, energy and careful
rehearsal to something worthwhile - like complete yet neglected
works.'

- Patric Standford

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