Yup - rhythm is the master...with or withOUT actual drums.
We had a sax sectional rehersal in Jazz band one day and our teacher made us experience the element of "swing" without the drums or bass. The rhythm comes from all areas of the arrangement, and eben without a steady backbeat - you can feel the groove .... IF you were born with the gift.
No ammount of study can teach you swing. You either got it, or you don't.
Swing's the thing !