To use the phrase deja vu in the opening sentence of a reflection on Crosby, Stills, Nash & Young runs the serious risk of incarceration by the cliche police but my odd experience of the last seven days or so might just win me parole.

In September 1974, not long out of school and two weeks before university, I joined around 75,000 others at the old Wembley stadium for one of the great bills of the decade, a pre-punk blast before the tables got turned over by Rotten, Strummer and their oiky ilk.

Not only did CSNY parade their headlining talents but the under-card was barely overshadowed. With the Band and Joni Mitchell the supports, only opener Jesse Colin Young looked like a make-weight, an after-thought, and even he was pretty hip for a couple of years around then.

But I would avoid such recklessly indulgent nostalgia, or at least keep it to myself, if it weren’t for a curious find on Amazon only last week. Looking for something else altogether, I spotted that there was now a DVD of that lost London extravaganza and, with a price tag of under a tenner, I could not resist.

CSN&Y ’74: A Long Long Time Ago – a gratingly clumsy nod to Crosby, I suppose – seemed to have a genuine stench of low-grade bootleg about it – no accreditation from a label you’d know, no reference to who had actually made the piece. But there it was, available online and, with haste, the purchase dropped through the letter-box.

Now, to load this verbatim account of a three-hour concert from getting on for 40 years ago, on to my computer, was a curious feeling indeed. A further over-used conceit all too quickly came to mind – here was a trip by time machine, no less.

Hardly surprisingly, I could not remember a single moment of the original occasion. Having bussed it to the capital from Manchester overnight and then taken a seat on the old football terraces, maybe around the half-way line, neither my head nor my location were well-placed to absorb any details of the action happening at one end of the huge ground.

This was a long afternoon and evening when that post-Woodstock vibe briefly revived in the early autumn, English sun and what went on on stage – noise, movement, announcements – was just an indistinct sideshow, a fleetingly colourful blur that may just have resembled a live gig of some variety, way off in the middle distance.

In those times before concerts utilised giant screens there was scant chance of you actually
being able to discern what was going on under the skies or under the lights. Yes, you’d know the songs – or most of them. But I had no idea, for example, that Joni Mitchell had joined the band for several of their performances.

So, to see a gig you’d been at for the first time, more than half a lifetime later, was both revelatory and disorientating. I was having an experience I assumed I would never have, rather like, to be slightly glib, the man who finds his 20/20 vision restored after seeing the world through astigmatic eyes until then.

And what of the DVD documentary? The credits, the context, are completely absent, so I’ve little of substance to share. It seems, though I cannot be sure, that Graham Nash was responsible for the film – though quite what that means when he was on stage for the virtually the whole gig, who can say? – but the group hated what they later saw and the piece was never, at least not until very recently, available in any format.

Were Crosby, Stosby and Nosby justified in their hyper-critical reaction to the footage. Well, to be fair, this is neither a classic rock’n'roll movie but nor is it a product without its rewards, particularly if you had any interest at the time in this now somewhat undersung supergroup, arguably the biggest of all American acts in their short heyday.

There are some hot moments – Stills turning his acoustic blues monster ‘Black Queen’ into a sub-Hendrix power trio bash and Neil Young singing a charming and, to me, unknown track called ‘Traces’, plus a blistering ‘Ohio’ to close when the war in Vietnam was still ongoing – and some ropey ones – a ragged and unconvincing ‘Carry On’.

But, if you’ll excuse the necessary subjectivity, for me, everything here was, in its way, fresh, fascinating and new: a small yet significant fragment of my personal story bizarrely restored if not quite to digital standards.

My musical tastes moved on rapidly after that though I still feel, like Kandia Crazy Horse as it happens, that Stills remains one of those unjustifiably sidelined rock gods whose work, with Buffalo Springfield, with this act, as a solo player and also as leader of Manassas, represented one of the most impressive surges of creativity over a period spanning less than ten years.

I was reminded, too, in the last month or so, of that wider LA scene, out of which CSNY and a remarkable generation of rockers and folkies and country stars emerged, as I almost salivated over a delicious coffee table tome that has just turned up entitled Canyon Dreams: The Magic and the Music of Laurel Canyon.

Written by that great raconteur of the pop epoch, Harvey Kubernik, it is a quite irresistible tour, in anecdote, interview and image, of the vibrant late 1960s/early 1970s scene when that quarter of Southern California was a veritable mecca of music, and the greatest US songwriting talents headed to the balm of the Sunshine State to share their melodies and their marijuana.

Canyon Dreams, published by Sterling at a ludricously low £20, actually spans a longer period, from the after-war rise of this scene to the post-Geffen & Roberts era, too, but its main focus is on a golden age of the Byrds and Joni Mitchell, Jackson Browne and the Eagles, of the Roxy and the Troubadour, and so much more.

In fact, this mouth-watering survey is an ideal companion to Barney Hoskyns’ 2005 tome, the more text-heavy but highly readable, Hotel California. Kubernik’s visual feast of album sleeves and archive photos, concert posters and period portraits perfectly complements that British journalist’s earlier tale when the lunatics not only took over the Asylum – they built it, too! – and, along the way, turned that confessional singer-songwriter style into a global phenomenon.