It reminded me of Carcassonne on iOS. One of the highest rated game apps and one of the best board game conversions for iOS. It launched at $5, never had a sale. When the iPad came out and they made the app universal they raised the price to $10. The app went 3 years and has only had a sale last December (because they released a new DLC).
Thing was that sale came as a total surprise. That was the app basically known for not going on sale, on a platform with a race to the bottom on prices and often frequent "free for a day" promos. It sold for $10 for the majority of its lifespan, and that was that.
Compare that situation to what is happening on PC where a game is either on sale, or you just wait 2 months for the next sale. It's damn near guaranteed, so why buy now?
I agree that this isn't a sales method for everyone. Jason makes pretty niche games that probably won't make that many sales in general, so it doesn't make sense for him to run sales in the first place. Plus his personal lifestyle is
rather unique. It seems like he doesn't personally care if he makes a fortune off a game. When your yearly budget is under $10,000 you don't have to sell a million copies of anything.
This method won't work for CoD, obviously. But it was interesting to think about. Knowing that Castle Doctrine won't ever go on sale, I am now pretty tempted to buy the alpha now when I know I'll be getting the best price.