[chrischen]

I assumed the article's definition of BS is stuff that is universally BS.

Frankly if something isn't BS, the reason can be properly explained. And if the subject can't understand the reason why, then he/she is not ready to do the work.

So whoever over-designed the O-rings must have had a good reason to do so. If he/she had a good reason, it is by definition no longer BS (it may still be boring grunt work). If not, then they were just lucky that it worked out.