His letters swarm willy-nilly across the page like ants on a sidewalk

Zinkoff never saw a blue line he couldn't miss. Over the line, under the line, perpendicular to the line -- his letters swarm willy-nilly across the page like ants on a sidewalk.

Hi,

Is it right to interpret the above as the following? Thanks.

Zinkoff missed every blue line ... his letters crawl crowdedly and messily across the page ...