OP is running a 10.0 car that likely 60's in the 1.3Xs and weighs 3200lbs...not a dragster that runs 1.0Xs or a 10.5 headsup car. This is apples to oranges.

In my car, with a similar size tire as OPs, running anything excessively low would cause the tire to wad over itself. I run 15-15.5 without issue, and my sidewalls are still okay by the time the threads are showing.