Crossword Genius

Motto of waiter, exhausted, needing G&T? (3,2,4,4)

Ross

I believe the answer is:

all in good time

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'motto of waiter' is the definition.
I know nothing about this answer so I can't tell whether it can be defined by this definition.

'exhausted needing gt?' is the wordplay.
'exhausted' becomes 'all in' ('all in' can mean exhausted).
'needing' says to put letters next to each other.
'gt?' becomes 'goodtime' (I can't explain this - if you can you should give a lot more credence to this answer).
'allin'+'goodtime'='ALL IN GOOD TIME'

Can you help me to learn more?

(Other definitions for all in good time that I've seen before include "Please be patient!" , "Soon enough" , "In due course" , "eventually?" , "No need to rush" .)

I've seen this clue in The Telegraph.
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