I told the story in overlong fashion here. The capsule version:
Setterfield claims that Adam can be standing in the Garden of Eden on Day 6 of Creation Week and everything works the same as it does now, despite light being 11 million times faster than now and the sun and the earth experiencing nuclear reactions speeded by a similar factor. That's why the earth and the sun "look" old according to Setterfield: when light was fast, nuclear reactions went fast.That could be a problem because Adam is getting bombarded with vastly more radiation than a person standing in a garden would be today. Setterfield's answer--never mind how he gets there--is to say that each photon has proportionately lower energy.
My main objection was that human eyes don't see photons of such low energy, since they are very long-wave. And I never got a convincing answer to why that's not a problem.
What if Adam's eyes were detecting the slower, less-energetic cosmic rays?