The sign of the cross: an oddity in 13th century England?

Making the sign of the cross in the British Isles might not be as pervasive and as old as previously imagined. The 13th century English chronicle known by the name of “Barnwell” (central to my ongoing doctoral thesis) has an intriguing testimony under the year 1221 AD:

“Petrus de Roches Wintoniensis (i.e Winchester) episcopus, quadam Dominica ante festum Sancti Michelis, in cathedali eiusdem civitatis ecclesia missam sollempniter celebrans, cruce se signavit; pluresque eius familiares, exemplo ipsius provocati, eodem signo se signari fecerunt.”

It might be taken to imply that bishop Peter’s household didn’t use to sign themselves during Mass (even less so at any other moment). This begs the question: if the bishop’s retainers did not do it, would the other laymen do it? Unfortunately, my knowledge of Christian gestural spirituality is very limited and I can’t take the matter any farther. But I do find it curious that the author would mention this had it not been a novelty for him too.