Although stride piano is often thought of as being a fast, lively style, there'a whole tradition of slow stride that's not as well known anymore. In fact, one of my Skype piano students was astonished when I played some slow stride for him and suggested that he play the jazz ballads he loves so much in this style. (He was astonished because another jazz piano "teacher" had previously told him that "you can't play stride on ballads.")
From the 1920s through the late 1950s, slow stride was one of the major ways to play solo piano ballads. (It may have started in the 1910s, but this is before solo jazz piano was documented on recording.) Jazz pianists played slow blues tunes using a slow stride left hand pattern, and they enjoyed playing the popular ballads of the day using the same technique. It produces a beautiful, relaxed sense of swing that makes me feel as if I'm floating on a cloud.
For inspiration, here's one of my favorite recordings of slow stride piano:
Ella Fitzgerald and Ellis Larkins: Imagination
Enjoy the journey, and "let the music flow!"
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