Final answer:
Sherlock Holmes did not deduce that the writer of the message was left-handed or a woman. He concluded that the writer was an amateur and had small, delicate hands.
Step-by-step explanation:
In Arthur Conan Doyle's story, Sherlock Holmes made deductions about the message based on his observations. From the evidence provided in the passage, Holmes concluded that the writer was an amateur and had small, delicate hands. However, there is no mention of the writer being left-handed or being a woman. These deductions were not made by Holmes based on the information given.