There are three central questions to the Harry Potter mania which drove the search for clues:
1) What exactly happened in Godric’s Hollow?
2) Where did Snape’s loyalty lay? and
3) How would Harry defeat Voldemort?
JKR's mystery-plotting style rests heavily on that old reliable magician’s trick: sleight of hand.
Misdirection is perhaps the most important component of the art of sleight of hand. Using misdirection, the skillful magician choreographs every movement in a routine so even the most critical and observant spectators are compelled to look where the magician wants them to. (source)
While laying her most important clues, JKR diverts the readers’ attention away from the clue and to her carefully plotted distraction. There are various methods she employs for this diversion, including some aspects that are not necessarily sleight of hand.
A Dozen+ Golden Eggs for Tricking Your Reader:
1) give meaningful names
2) use of "running bits" here and here
3) divert with action or a joke
4) distract with high emotions
5) camouflage by use of myths and folklore
6) hide in a list
7) discredit the witness
8) drop in dreams
9) mark with colors and themes
10) mirror parallels
11) reverse expectations
12) juxtapose the villain with the scene of the crime
13) character lies or misperceptions
Play fair with your reader. You must leave clues.
Plotting a mystery is a very fine balancing act. If the author leaves insufficient clues to give the reader a shot at solving the puzzle, the reader feels cheated. However if the author makes the clues too obvious, the reader also feels cheated out of the pleasant surprised “gotcha” at the end. The evidence is overwhelming that JKR has walked that tightrope gracefully and masterfully and has not cheated her readers, but left them with many hours of happy sleuthing, and definite pleasant surprises.
We'll break apart each of these steps in separate posts over the next few months. I will not do them back-to-back, but will label them all under "Mystery Plotting" and "Clues" so you can follow the thread.