Faust's bind is desperate, with many reservations (3,3,4)
I believe the answer is:
ifs and buts
'many reservations' is the definition.
'faust's bind is desperate' is the wordplay.
'is desperate' indicates anagramming the letters.
'fausts'+'bind'='faustsbind'
'faustsbind' with letters rearranged gives 'IFS AND BUTS'.
'with' acts as a link.
(Another definition for ifs and buts that I've seen is " Uncertainties".)
I've seen this clue in The Guardian.
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