The general theme with these shapes is the dominant 7th sound, which is essentially a major chord plus a b7th. This is a great way of injecting some ‘blues’ flavour into your chord progressions ...

Use our acoustic guitar ... blues. Bm7 is just the ticket for a moody minor blues; if you improvise around this chord, try using the D7 shape four frets higher to create a Bm7 and F#7 progression.

which can be looked at as implied F7 chord. Now, one could easily play licks based on the F blues scale (F, Ab, Bb, B, C, Eb) over the entire progression, and it would work well. But in this ...