Michael,
No, you should continue to use the FGWorkingHoursBar to highlight/differentiate the working-hours from non-working hours.
So, once we get rid of the bars we will render both the scenarios (whether or not the tasks start in non-working time or not) the same way - and this would be similar to how we render now with TasksDontStartAndEndInNonWorkingTime = false. The current "true" setting is not only buggy, but was also unnecessary, so we will remove it.
Thanks
RadiantQ Support