Beset by second performance issue, engineer's dealt blow (7)

I believe the answer is:

swatted

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'dealt blow' is the definition.
Although both the answer and definition are past participle verbs, I can't see how they can define each other.

'beset by second performance issue engineer's' is the wordplay.
'beset by' means one lot of letters goes inside another ('beset' could historically mean 'cover').
'second performance issue' becomes 'sed' (I am not sure about this - if you are sure you should give a lot more credence to this answer).
'engineer' becomes 'Watt' (James Watt, s7d6-s8s9).
'sed' placed around 'watt' is 'SWATTED'.

Can you help me to learn more?

I've seen this clue in The Independent.

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