One of the weirdest theories ever!

I used to work for a guy who's main theory in his pricing practices involved 3's, 6's and 9's. He bestowed this gem on me one day when I was updating some of the pricing on the website that I used to run. Now, I thought he smoked way too much pot that morning or something or maybe that he was just pulling my leg. Here's how he figured it, if something should be selling for $425 he'd bump it up to $439 because of the 3. The system worked for other prices as well, like $450 would be bumped to $469 and $480 would bump up to $499. Sorry, I digress, what do you all think, was he a bit crazy or is the theory sound? Let me know.