Considering Fleetwood Mac’s enormous popularity in the 1970s, which can be traced to the moment Lindsey Buckingham and Stevie Nicks joined the waning band, Buckingham would have to rank as one of the most underrated guitarists in rock. He is also one of the more unorthodox.

An ex-folkie who displays his acoustic fingerpicking on “Landslide” and “World Turning” from the group’s self-titled 1975 comeback, Buckingham’s “technique” on electric lead was closer to clawhammer banjo – flailing away with pickless fingers, which usually ended up bloody by the end of a set. But his sensibility was best exhibited on “I’m So Afraid,” from the same album, which became his extended showstopper onstage. The licks were simple, but with Lindsey’s sense of dynamics (and a super-long setting on his delay), the effect was mesmerizing.

Mac’s three albums from the height of the band’s popularity, repackaged with bonus material, reveal the changes the group was undergoing collectively and Buckingham’s artistic growth in particular.

On the heels of their unexpected success, the band was in the midst of broken relationships and divorces. But instead of spelling the demise of the band, the tension fueled a startlingly revealing album that would eventually sell 30 million units worldwide.

The band’s inner turmoil was evidenced in lyrics such as “Players only love you when they’re playing,” “I’m just second-hand news,” “You can go your own way,” and “I can still hear you saying you would never break the chain.” The fact that the three songwriters wrote alone was nothing new; they’d seldom collaborated. Ironically, all five members had a hand in composing “The Chain.”

In addition to his solo fingerpicked country ditty, “Never Going Back Again,” Lindsey’s showcase this time was the herky-jerky “Go Your Own Way.” And for the Rumours reissue, a full second disc was needed to house the outtakes, jams, and songs that didn’t make the cut. The outtakes aren’t particularly revealing, except to show that the finished takes were indeed more fleshed out and heartfelt. “For Duster,” an instrumental blues jam named for early Mac cohort Duster Bennett, shows the band having a good time in the studio.