[mindslight]

Let's not let different characterizations get in the way of our common understandings...

The local architects would follow the leading architects from their industry, but lumping it into "mass media" was probably a bad characterization. I'd describe it as as a kind of communication-based centralization, regardless of whether specifically enabled by periodicals, telegraph, train, etc.

You could accomplish the same thing with a more-local architect at the town or city level, but would the smaller gains pay off?

[dalke]

When it is slow enough, that's called a culture shift. Your piano seller wants change fast enough to call it personal profit. Mass-produced pianos require mass media as local changes won't pay off the cost of the production machinery. Might as well stay with local craftsmen.

"Communication-based centralization" includes Louis XIV of France's centralization at Versailles, yes?