Gets pint — opens out revealing means of advancement (8,5)
I believe the answer is:
stepping stone
'means of advancement' is the definition.
(I've seen this before)
'gets pint opens out' is the wordplay.
'out' indicates an anagram (out can mean wrong or inaccurate).
'gets'+'pint'+'opens'='getspintopens'
'getspintopens' anagrammed gives 'STEPPING-STONE'.
'revealing' is the link.
(Other definitions for stepping stone that I've seen before include "feature across stream?" , "means of advancement" , "means to get better" , "Aid to gradual progress" , "Footrest in river" .)