Breaking News: NASA was right, I was wrong. Should have moved that decimal one more time to the left. Instead of 6%, it should be .668%. With pressures of up to 15 millibars or 1.5% in other locations, 1% is a good average. This is still misleading. Gravitational influence must be understood.
For example, if you stripped the Mars atmosphere away and replaced it wth Earth’s atmosphere; the surface pressure would drop from 1000 millibars to 382 millibars. Same atmosphere. What happened? It was less compressed. Now, instead of 100 miles deep, it’s 230 miles deep, estimate.
Most likely they are using the KISS method. (Keep it simple stupid.) They would have to understand this with atmospheric interface and drag.