Doesn't keep the orchestra together (8)

I believe the answer is:

disbands

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'doesn't keep the orchestra together' is the definition.
I can't tell whether this defines the answer.

'doesn't keep the orchestra' is the wordplay.
'doesn't' becomes 'diss' (I can't explain this - if you can you should give a lot more credence to this answer).
'keep' means one lot of letters goes inside another.
'the orchestra' becomes 'band' (large musical group).
'diss' enclosing 'band' is 'DISBANDS'.

Can you help me to learn more?

I've seen this clue in The Globe and Mail.

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