[rcxdude]

"time is of the essence" is more of an example of jargon, which is something different from the drafting style. It's true that it's not particularly accessible, but it's useful because it captures a specific technical meaning in a short phrase. (Specifically, 'time is of the essence' means that any timelines specified in the contract are strict: missing by even a few seconds is a breach even if the delay is not material).