I think the study was worthless. It is extremely difficult to note the differences between people that have healthy eyes. The brain and eye can adjust for a LOT of things under many varying conditions. That's how the system is intended to work. However, if you have eye damage, your brain and eye CAN'T make this adjustment. It is those who have physical issues with vision that can tell a researcher whether this thing works better than that thing.
If they want a study that actually tells them something, they should recruit people with similar eye damage to compare the screens.