The treading through the review of the literature is beginning to pay off with some statements. I think my favorite is the moment where Hutton skewers the Frazerian notion of rural industrial revolution Britons being slavishly mechanical preservers of Pagan customs they no longer understand as condescendingly elitist.
Some more nails in the coffin of a continuous British Pagan religious practice: Ceridwen? Hern? Literary figures back-projected onto ancient British Paganisms, and not examples from a continuous Pagan religion. Cauldrons? Probably used by ancient Pagans in worship, but also prestige items for early Christians. Witches as Pagans? Well, it depends--are we talking Scandinavia, Italy, or Britain and what era? But most likely they were Christian-based magical practitioners (i.e. the "Cunning Folk").
Does this mean much for the modern NeoPagan who chooses to venerate Ceridwen or Hern? Not really (other than putting the theological pedigree into tatters). Hutton pulls a Gödel-Escher-Bach move, steps back from the archeological evidence and points out that over the thousands of years spanning the record, the precise names and rituals may change, but the underlying religious impulse that creates them stays fairly constant.
One example sited is the Abbots Bromley Horn Dance. The dance as it's done today is a perambulation with reindeer horns done to raise moneys for a church parish. It's one of the last perambulations of its kind, having survived the Reformation, from about the 16th century (at least) when hobby horse dances like it were common. Does the Abbots Bromley Horn Dance go back to paleolithic times? Hutton concedes that there's no proof, but implies that it might, because it falls into a class of folk customs (Greening Homes at the Winter Solstice, May Day Poles, Harvest Festivals) that follow a seasonal pattern and which the expression of which likely do go back to ancient times .
As someone who danced a Pacific Northwest version of the Abbots Bromley for about ten years every September at the Oregon Shrewsbury Faire, I can attest to both the spiritual impulse and its lack in the dance. Sometimes it was just a dance with deer horns on sticks and we were expected to perform it as part of the faire's entertainment. Occasionally, though, it became a part of something larger (at least in my experience), and I had the sense that the dance extended ahead and behind the time and place where we were (and as we were primarily performers and not a spiritual/religious group, straying this close to ritual raised ambiguous feelings for me).
Next up... Deities!