Custom fields opion in the Time section of display_options.php page defines whether or not to show time custom fields in a list of existing entries for each day.
Custom fields in display options
It turns them on or off for display in their entirety, no matter how many time custom fields are defined. For example, if two custom fileds exist then both will display if you enable the option. The screenshot below explains it. This option helps to control how much horizontal space is needed to print entires.
