And he certainly seems to be having a good old time. Part of his pleasure seems to reside in just fucking with people's expectations, with the categories they wanted to put him in, but he wasn't just being malicious: he was making up the rules for how to survive as a compelling and responsive artist in the pop sphere as he went along, and there weren't any relevant models for him to follow. (Sinatra? Presley? They didn't write their own music. Lennon? He was behind the curve whose arc Dylan was busy tracing.)
How long Dylan could have kept up the crazed pace documented in these photographs is something we can only speculate about because in 1966, he had the motorcycle accident that took him out of public circulation for two years. When he re-emerged, he seemed uninterested in, or exhausted by, or simply bemused by the modern pop world he had helped forge. He disengaged from it, internalized and for a while became a folk fabulist (John Wesley Harding) and a happy country picker (Nashville Skyline). At the time, these new incarnations seemed "authentic," "natural" responses to "plastic" popular culture, but they turned out to be simply the first in a new line of Dylan identities, some of which led to great work (Blood on the Tracks, part of Desire, Infidels, Oh Mercy and Time out of Mind, and some things like "Series of Dreams" from The Bootleg Series) and most of which led to dead ends, bad lifeless records, an aesthetically disastrous religious conversion and general flailing about in the void.
But then again, Dylan helped define what the void means for us. He looked at the vacuum in the eyes of the mystery tramp, and it hooked him like the eye of the Ancient Mariner. It blasted something out of him like lightning blasts a tree, left him permanently rootless, grasping for some kind of hold on himself and his music.
"The pure products of America go crazy," wrote William Carlos Williams. Yes, and if they're lucky, their madness takes the form of Bob Dylan's.