Is “Inversely Proportional” the right term here?

Question

The effort required to design something is inversely proportional to the simplicity of the result.

-Roy T. Fielding, http://roy.gbiv.com/untangled/2008/rest-apis-must-be-hypertext-driven

In the context of the article, it is obvious that Mr. Fielding is trying to say that the effort required to design simple things is greater than the effort required to design things that are complex.

Wouldn't "inversely proportional" indicate that if something takes more effort to design, it would be less simple though?

Wouldn't it make much more sense to say:

"The effort required to design something is directly proportional to the simplicity of the result."

or

"The effort required to design something is inversely proportional to the complexity of the result."

Answer 1

Mr. Fielding's version is plain wrong, absolutely.

Your version is technically correct but muddled.

In their efforts to sound sophisticated, some folks forget that the main purpose of stringing words and sentences together in an article is to convey the meaning.

Why not just say:

The simpler the desired result, the more design effort required.