Attack on studies as military training exercises (7,7)

I believe the answer is:

assault courses

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'military training exercises' is the definition.
I don't know anything about this answer so I cannot judge whether this works.

'attack on studies as' is the wordplay.
'attack' becomes 'assault' (synonyms).
'on' means one lot of letters go next to another (in a down clue, letters appear on others).
'studies as' becomes 'courses' (I can't explain this - if you can you should believe this answer much more).
'assault'+'courses'='ASSAULT COURSES'

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I've seen this clue in The Telegraph.

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