"There's great coral to be seen in the tropics, the Philippines etc. in water degrees warmer than the GBR is in."
A meaningless argument, the species of corals in those regions have had thousands of years to adapt to the warmer waters in that part of the world.
If water temperatures increase above the typical range they too will experience bleaching as with what happened in the Maldives where the average water temp is similar to the Philippines.
