AOTG – interesting although the page isn’t very clear.
For example near the top it says “If your baggage is through checked and you already hold a boarding pass for your onward flight, then simply follow signs for Flight Connections. There is no need to clear border control or Customs. “
However some way down the page it says that if connecting to a domestic flight you do need to clear border control presumably even if you have a boarding pass and your baggage is through checked.