Looking at the wrong data is pretty bad, and the BSOD should never be tolerated in a rig data package.
Still, 'older' hands would likely rely on gauges and pit levels by eyeball rather than believe a computer which tells them something different than their observations, just because they don't trust the computers anyway.
This might have led to the disagreements which were alleged to have occurred between crews and BP management, and I can see where someone might be inclined to blow off readings which indicated adverse conditions in the wellbore as a computer error or miscalibration.
The critical error would be in not verifying that either the computer readouts were in error or that the readings were indeed correct before proceeding, especially when considering the potential for disaster. While the driller's console is an important one, there should be multiple redundencies onsite (or on the rig), not just that one display.
I wonder whose program they were running?