Watch the b7 to 7 to 1 Via HO online guitar lesson by Brad Carlton from Guitar Lab: Bulls Eye Blues Riffs

Example 6 inserts the 7 as a chromatic connection between the b7 and 1. By itself the 7 is a weak tone over a dominant 7 chord. But when it is used as a connector, is effective at creating that ultrasmooth sound common in jazz riffs.