But you are using the material played by The London Symphony Orchestra in general.

In this case the term "material" meant the stuff that has been played by The London Symphony Orchestra. (the original)
["equipment" stands for hardware: amplifier, CD-player, speakers, headphones; software is software]

You could have decided - as you have worked on the tracks in segments - to put in some parts played by another orchestra (a "copy"). That would have changed the track in general of course. But we are talking about an Optimum Edition, aren't we?! An optimum could be achieved by surpassing the original by a copied segment.

e.g.: I don't know if you know this early DDD-recording from 1990 (http://www.amazon.com/John-Williams-Conducts-Star-Trilogy/dp/B000002712).
It contains an extended "Throne Room and Finale" track (7:57 min.) and it might includes tracks that might be "optimum". However "it's a Sony" ...

"For this recording 20-bit technology was used for 'high definition sound"." (source: CD-backcover) ... those were the days when they advertised VHS-recorders with a "HQ"-mark - "high quality", of course.