On the subject of gaps since I had some stuff up here. ES since early 2013:
# Gaps Up = 733 => Closed the same day = 47,5 %
# Gaps Down = 553 => Closed the same day = 51,7 %
This excludes smaller gaps (+/- 2,5) and only counts a full close (excluding those -1,0 points from a fill days) - but...