Wouldn't it be faster to use the dragon stone to enter and exit the battle tower, rather than using the teleporter? Going up and down the elevator in the throne room would be at least as much of a delay as the 5 second cooldown on using the dragon stone again after leaving the battle tower.
Loading times may also be faster returning to a small cave or house in Aleroth rather than an area large enough to have a teleporter shrine. On my Xbox, it takes 12 seconds to enter the throne room; leaving the battle tower, it takes about 28 seconds to return outside on Sentinel Island, but only 10 seconds to return to the interior of Gobie's house in High Hall (have not tried in FoV yet).
