Question

Holmes says Watson tends to "somewhat embellish so many of my own little adventures." In this case the word "embellish" means to add with interesting, but not essential, details. Explain how Watson's habit of embellishing both helps and hinders a reader's attempt to solve the mystery before Holmes does.

Answer 1

First let's understand a Sherlock Holmes mystery and how it is structure because that will give us some clues to answering your question. The basic framework of a Sherlock Holmes tale (and many if not most or all mystery stories) goes like this:
1. Setup - This is where you get the initial information about the mystery like who the characters and suspects are what exactly happened and what Holmes is trying to figure out. This stuff generally occurs in the introduction at the beginning of the story.
2.The soup - I call the middle the soup because this is where all the good stuff is, the action, the clues, the mystery, all unfolds in the soup, but like soup, it can get muddled and murky. This is where Watson's 'embellishing' comes into play. The soup is also where the reader is continually trying to piece together the clue to figure out 'who dunnit'.
3. The reveal - The reveal is where the reader finally finds out the solution to the mystery and if they had figured it out during the soup. The reveal always plays out with Holmes explaining what happened, who did it, and how he knew.

Just knowing the structure of how a Sherlock Holmes mystery is laid out should probably be enough information to answer your question, but if not I'll help you by framing the question in a different and simpler context.

Think about this question like this: Say you want to know where someone was born so you asked him and he started out telling you where his parents were born and how they met, how many siblings he has and when they were born, anecdotes about his childhood and how he got along with his siblings, all before telling you when he was actually born.

The easy question to answer is, how does all that extra information that he gives you hinder you from finding out his age? The harder question perhaps is, how could that information that he gives you help you determine his age before he tells you?