The most common and most likely answer to this crossword clue is the 3 plus 7 letter word ICE DANCING
I've seen this crossword clue in Financial Times
I
C
E
D
A
N
C
I
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G
More clues leading to the result ICE DANCING
Buddy explains!

The straight part
We know that "Wherein couples slide towards point-scoring" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case wherein couples slide towards point-scoring = ice dancing.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.