Second eleven winning after comprehensive instruction given by captain? (4,5,5)

I believe the answer is:

full steam ahead

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'instruction given by captain?' is the definition.
(instruction a ship's captain might give)

'second eleven winning after comprehensive' is the wordplay.
'second eleven' becomes 'steam' (I can't justify this - if you can you should believe this answer much more).
'winning' becomes 'ahead' (I've seen this before).
'after' says to put letters next to each other.
'comprehensive' becomes 'full' (synonyms).
'steam'+'ahead'='steamahead'
'steamahead' put after 'full' is 'FULL STEAM AHEAD'.

Can you help me to learn more?

I've seen this clue in The Telegraph.

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