Here's something strange--possibly meaningless, or maybe not.
When θεωρίαις passed into Latin as theōria, it was reduced to a single definition: contemplation/speculation. Festivals was lost.
When I looked at the bibliographies of Hicks, Yonge, and Mensch, I noticed this; Yonge spent most of his translating time working on Latin texts, and he uses the word θεωρίαις in the Latin sense of contemplation. Hicks and Mensch, on the other hand, spent most of their time working on Greek texts, and they use festivals.
Do three trees make a row in this case, or am I just out of my depth per usual?