Much better having unexpected U-boat victory described by expert (1,3,5)
I believe the answer is:
a cut above
'much better' is the definition.
'a cut above' can be an answer for 'better' (thesaurus). I am unsure of the 'much' bit.
'unexpected u-boat victory described by expert' is the wordplay.
'unexpected' is an anagram indicator.
'victory' becomes 'v'.
'described by' indicates putting letters inside (to describe can mean to form an outline).
'expert' becomes 'ace' (ace can informally mean very good).
'u'+'boat'+'v'='uboatv'
'uboatv' is an anagram of 'utabov'.
'utabov' going inside 'ace' is 'A CUT ABOVE'.
'having' is the link.
Can you help me to learn more?
(Other definitions for a cut above that I've seen before include "Noticeably superior to" , "Something superior" .)