Hi, article author here. This was more a comment on the verbosity of Google Closure's syntax. If you're not familiar with it, to get the most out of the closure compiler, you have to add type annotations in javascript comments for pretty much every function parameter, return value, constant, etc. Otherwise the compiler's static analysis doesn't really have much to work with. This makes it kind of a pain to javascript devs who are not used to this sort of thing.

Coming from Java, I probably found it a little less annoying than most javascript devs. Although in Java (as I mentioned in a footnote) you have really powerful and mature tooling like Eclipse, which--whatever else you think of it--does really help with Java's general verbosity. You're not going to find the same sort of tool help for dealing with Closure javascript.