If it is idiomatic what is the phenomenon or the social enigma it is trying to simplify or explain. It is more than just a pun or a crossover in history. It is a sense of self that is fluid between the east and west never settling in either place for too long. The flight of horse is a bit of a contemporary Retelling of Kipling’s famous poem 

the east is the east and the west is the west 

and never the twain shall meet.

When one encounters an artifact from the west or the east that has somehow crossed over the boundary and they are on the precipice of trying to ascertain an origin or context for this thing they are experiencing the flight of horrors.

It is criticized today as a appropriation of culture. When I chef creates a dish from an external culture and claims it as their own.  A dancer may practice the moves of an art in which they were not born into or top like the belly dancing club of the suburbs.

The Egyptologist and historian may know that Horace fled with his mother Isis in fear that his uncle Seth would kill him. 

However the western classicist may consider Horace as an old Roman name Without any specific or known origin and also with no interest in seeking that origin.