The most common and most likely answer to this crossword clue is the 6 letter word DOUGHY
I've seen this crossword clue in The Guardian
D
O
U
G
H
Y
Buddy explains!

The straight part
We know that "workable at a stretch" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case workable at a stretch = doughy.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does DOUGHY mean?
DOUGHY adjective- Having the characteristics of dough especially in appearance or consistency: as