Punctuation Marks and Traffic Flow

From Roy Peter Clark in the book “Writing Tools”:

If a period is a stop sign, then what kind of traffic flow is created by other marks. The comma is a speed bump; the semicolon is what a driver education teacher calls a “rolling stop”; the parenthetical expression is a detour; the colon is a flashing yellow light that announces something important is up ahead; the dash is a tree branch in the road.

h/t Mike Pope, who posted this on Twitter.