Meaning: average talent with no special skills


Rewrite 1: a mean hauler of sails who can't tie off a knot
Rewrite 2: he can swing a mean hammer but can't hit a nail
Rewrite 3: all tool belt and no tools
Rewrite 4: good at coloring inside the box but can't stay in the lines
Rewrite 5: Mr. Handy, Mr. Thumbs


Comment: A "jack" was an average seaman while a "master" was a highly skilled craftsman on a ship, so this idiom originates with the early sea service. A jack might be good at doing general duties on ship, but he wouldn't be rated a master until he could do extraordinary work. I started by trying to rewrite these to give some sense of those skills or lack of said, then generalized from there.


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Sounding like a sea dog
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