He hasn't really achieved a very prominent position in the mac app store though. The post there shows he is 6 in the 'developer tools' category. I suspect this is one of the least used / lowest sales of any of the sub-categories. Most developers probably aren't looking in the app store for their tools, they already have them, and even if they are, developers make up a small percentage of mac users. Perhaps, only 1% of all mac owners are potential customers... Even less really because they must be mobile developers to make use of his application.

His sales vs position has nothing to do with the appStore and everything to do with being in an extremely tiny niche market.

Achieving a prominent position in the Mac App Store in a category like Developer Tools isn't worth many sales. That doesn't surprise me in the least.

Going against the old adage of "Don't dig for gold; sell tools to miners"?

That works great, unless said miners have an almost ridiculous quantity of tools just lying on the ground waiting for someone to clean them up a bit and start using them.

But there's a big, big pile of gold (normal iOS or even Mac users).

Developer tools can't be an easy market to succeed in. You aren't going to get many impulse buys.

Yeah but the gold have been dug for awhile now, plus there are competitors with just as easy access to the market and his is only a little different from the competition.