In the book that accompanies Alpha Mike Foxtrot: Rare Tracks 1994-2014, a four-disc collection of rare and non-LP recordings by Wilco, former Reprise Records publicist Bill Bentley admits that no less a legend than Doug Sahm thought he was making a mistake when, after Uncle Tupelo abruptly and acrimoniously broke up, Bentley opted to work with Jeff Tweedy's new band rather than Son Volt, Jar Farrar's post-UT project.

"Come on, Bentley, you gotta go with the other guy," Sahm said, "he's gonna happen." Which was certainly the conventional wisdom when Wilco and Son Volt launched in 1994 -- most fans seemed certain that Farrar was going to go on to a brilliant career on his own, and Tweedy's band would be a fine but lesser commodity.

But those bets were off after Wilco released their ambitious, game-changing second album, Being There, in 1996, and in the years that followed, it became clear that Tweedy was a stronger songwriter, a more imaginative sonic visionary, and a keener judge of collaborators than he'd had the chance to show in Uncle Tupelo.

Two decades on from their debut, Wilco have created a large and impressively diverse body of work, and Alpha Mike Foxtrot is a massive odds-and-sods collection, bringing together 77 tracks from singles, promo releases, movie soundtracks, bonus discs, and downloads from Wilco's website.

Alpha Mike Foxtrot plays like an alternate history of Wilco, and most of what's here is every bit as satisfying as what the band delivered on its first eight studio albums, if more idiosyncratic; it traces the evolution of the band from early solo cassette demos Tweedy cut in his living room to extended workouts from the lineup that solidified after the release of A Ghost Is Born, as Wilco grew from a spirited alt-country combo to a rock band as adventurous and eager to innovate as it was engaging and tuneful (Tweedy's simple but powerful way with a melody is the surest unifying factor that holds these songs together).

And the plentiful live tracks here demonstrate how willing Tweedy and his bandmates have been to give their songs new shapes on-stage (a ten-minute live recording of "Spiders [Kidsmoke]" is a tremendous showcase for Nels Cline's stellar guitar work), and there's a fistful of studio tracks that didn't fit on an album but sound splendid in this context, especially the Replacements-styled "Student Loan Stereo," the soulful "The Thanks I Get," and the faux-live pop/rocker "The Good Part." In the strictest sense, nothing on Alpha Mike Foxtrot is unreleased, but there's a lot here that's never been available for general public consumption, and while the sheer bulk of this set means it's most likely to be heard by hardcore fans, anyone with a genuine interest in Wilco will find a lot of great music that fell between the cracks on this set, as well as a fascinating map of the many roads Wilco did and didn't take.