I can report anecdotally that the traffic on Urban Highway 15 (ie. Donovan/White Swan/Hillsborough) has not noticeably decreased as a result of SH20 opening nearby. It can still take around 5 mins waiting before I'm able to pull out of my driveway if I'm going across traffic during peak times.
With regards point 1: Didn't Jesus heal the gay centurion's lover? Matthew 8:5-13 and Luke 7:1-10