If one was gonna get all writerly and pretentious about it, one could say that the Jerry Garcia Band was the guitarist’s form of practice. Not rehearsal, that is, so much as the thing he needed to do everyday, simply as a mode of being. And if he couldn’t do it with the Grateful Dead, it was imperative to do it with somebody else. Let It Rock, the latest from the still-somewhat-untapped Strategic Solo Garcia Reserve, is drawn from a layer of Garcia’s practice previously undocumented by official release: the short-lived Garcia Band lineup featuring British pianist Nicky Hopkins.

A permanent fixture on the British rock scene (he played keys on “Revolution” and “Sympathy For the Devil,” not to mention most of the Kinks’ singles) before emigrating to the Bay Area to record with the Steve Miller Band and join Quicksilver Messenger Service, Hopkins brought country inflections back to Garcia after the latter’s few productive years working with R&B/jazz-head Merl Saunders. The reason for the band’s short duration and under-documentation is pretty obvious from the go: the lineup doesn’t entirely click. Hopkins sounds pretty totally sloshed, and—according to the liner notes—he was. (And, to be fair, the liner notes also point at Hopkins’ poor health as the source for the former.)

By some standards, this is only a minor set-back.

Over a year into the Dead’s hiatus and still some seven months away from returning properly, Garcia is in pretty decent form. The phrase that jumps to mind is “effortlessly casual,” though one also imagines that, in fact, that’s the only way to be casual. Whatever, Garcia is ace at it, and pulls it off while sounding sweet, melancholic, musical, and—in places—telepathic. Exactly halfway through “Let’s Spend the Night Together,” the set’s 19-minute centerpiece jam, he drops out for a minute to give John Kahn space for a bass solo, and when Kahn demurs after a few phrases, Garcia swoops back in, developing his next lead moves directly out of Kahn’s phrases.

The tunes are mid-tempo and the jams float in the slow-burn between R&B and reggae, a bar band default circa ’75, probably. Most hover around the 10 minute mark. Sometimes, like Allen Toussaint’s “I’ll Take A Melody”—still only about half-year into Garcia’s solo repertoire—the band flows naturally around the changes, dropping into a perfectly languid zone by the end of the jam where Garcia is able to hover through his scales. (Garcia would chase these moments more effectively over the next few years with the replacement of Hopkins by Dead keyboardist Keith Godchaux.) In a lot of places on Let It Rock, though, the band simply doesn’t sound sharp. On Jimmy Cliff’s “Sitting Here In Limbo” and Garcia’s own “Sugaree,” two staples of the Garcia solo repertoire, the band sounds plumb sluggish. Or, perhaps, slugged. Though one can put the blame on Hopkins’ piano (especially on the former, where it sounds like it’s drooping over the song), it’s hard to put one’s finger on exactly what is causing the malaise. Perhaps it was just the vibes. (Eventually, on “Limbo,” the band just embraces the sleepiness.)

And, given the casualness of the formula Garcia was working with, one can only imagine him reacting with a gentle shrug of his beard. So it didn’t work. Big deal. Garcia got to blow on a few new tunes (Hopkins’ “Edward, the Mad Organ Grinder,” first recorded by Quicksilver, gets into some pleasantly dense changes), it was probably a pretty decent time, and he got to play, which might’ve been the only mission that mattered.