A lesson in the common practice of simplifying the music notation for shuffle music in order to make the score easier to read…
For example, listen to Frank play a snippet of blues shuffle music…
In order to capture the shuffle rhythm accurately using music notation, the score might look like this (using a 12/8 time signature)…

It also might be written like this (using a 4/4 time signature)…

While a fairly accurate representation of the rhythm, the notation above looks quite busy and is indeed fussier than necessary. And so, it is common practice to simplify the notation by simply using “straight” eight notes as follows, with the understanding that the eighth notes in either arm need to be “shuffled”…

Notice how much easier it is to read this shorthand notation!
But don’t forget: The notation looks “straight”, but its rendition might sound something like this…