Does no more than erroneously post a letter (5)

I believe the answer is:

stops

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'does no more' is the definition.
I can't judge whether this defines the answer.

'erroneously post a letter' is the wordplay.
'erroneously' is an anagram indicator.
'a letter' becomes 's' ().
'post' with letters rearranged gives 'stop'.
'stop'+'s'='STOPS'

'than' acts as a link.

Can you help me to learn more?

(Other definitions for stops that I've seen before include "Posts (anag.)" , "Ceases" , "Prevents" , "Ends" , "Discontinues" .)

I've seen this clue in the Evening Standard.

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