Ever wanted to remove a driver health configuration completely but found that the "Delete" button on the "driver health configuration" tab in iManager does not do it ? Well, just move to the next tab:
go to the "Driver Manifast" tab on iManager's driver properties page
tick the checkbox to "Enable XML editing"
delete the <health-config> XML node from the manifest
restart the driver
refresh the driver overview page in iManager
and iManager will not display the traffic lights next to the driver icon anymore.