That being said, I work in engineering with some brilliant fellow Christians who are unfortunately snared in this lie.
The point? The two most "hard-core" YECs are among the best minds I know when it comes to their jobs - which are very technical and and require fluency in electrical engineering, physics, and a slew of other areas.
This fantasy may be harmful in some ways but as an Ex-Navy Nuc who knew a whole lot of people like this it does not necessarily mean they are total incompetents or idiots.
I'm sure they are good at what they do, but would you honestly want them working in other scientific fields where the age of the cosmos is important? How do they justify a young Earth while working with elements that have provably been around for millions of years?
Like Kirkwood pointed out earlier, if someone believes the universe is only 6,000 years old, how do they explain stars that are millions of light years away? They obviously wouldn't cut it in the field of astronomy.