Swing

I assume when you say "swing setting" you are refering to a non programmable thermostat that has a heat anticipator rather than a programmable tstat that allows one to set a specific number of cycles per hour. Setting the anticipator allows you to tighten or expand the temp variance (probably with a degree or so) that a thermostat will shut down, allowing for the residual heat from a radiator to make-up the difference and minimize over-shooting the set temperature in the space.