Player1 I definitely agree that tempo is connected to heart and soul!
But at the same time, physically, it makes a lot of sense that it is also connected to your heart beat, and to your sort of overall mind set, level of calm etc.
And I really felt how just reminding myself to s l o w d o w n ... reminding myself that it's the end of the day, that my piano time is not the same as my work time.... just letting go of that high-pressure feeling, made a huge difference.
I think these are different from the heart and soul that you're talking about.