[throwawayjava]

> the main argument for project-based learning is ability to make learning interesting

James already addresses this assertion in the very first sentence of the blog post. And the second sentence.

[monkpit]

Which first sentence? The first sentence doesn’t have anything to do with that argument. Neither does the second.

[throwawayjava]

The first two sentences EXPLICITLY state the type of arguments that James is responding to. Click on the links in those first two sentences and read the arguments.

The "main argument" of those posts -- i.e., the posts James is responding to, is not that "project-based learning... make[s] learning interesting".

That may be your main argument, but it's not the argument that the people who James is responding to are (mainly) making.