I've been listening to Etta James to soothe my inflamed prostate lately. It doesn't help but I am impressed with the presence this woman exudes on her recordings. I actually have the sheet music for Saint Louis Blues in a songbook by Bob Wills and I don't think any notation of Db13 or eb7/C can approximate her inflection, timing and dynamics. No, that's called "Soul" and you don't write it down on paper.
This is basically a 12 bar blues but it doesn't sound that simple because the emotion she's expressing is timeless and intangible. That piano lick is so delicious but with no piano again it's like another untouchable song. I'm almost depressed enough to sing this song with enough soul to do it justice. Etta died recently. RIP