Of course it's not.
Cutts seems to be under the mistaken impression that hyperlinks were invented to provide source data for his employer, and that if his employer now chooses not to pay attention to some of them then the rest of us won't either.
In reality, if there's a link in the guest blog post, people reading that post can follow it. If it's a popular blog and an interesting post on it by the guest author, probably quite a few readers readers will.
Matt knows his audience and doesn't have to spell out everything to the nth degree--when he talks link building it's 100% of the time page rank related.
When they start giving out blanket advice about what people "should" do, particularly when the advice is as self-serving and frankly laughable as it is in this case, I find it increasingly difficult to give them the benefit of the doubt. I suspect they damage their credibility a little more every time any of them speaks or writes this way.