Judging by the examples you cite with which I am familiar, you would have to conclude that the word "weak" is just a lazy form of abuse when someone can't bother to be more precise.
If you take TOC first hole, Mark Ferguson implies that it might be weak because (he thinks) it is easy (in which case easy is the right word!). Actually, I agree with Sean - it is an excellent hole because it gets you into the course in a manageable way, and is probably slightly more difficult than it appears.
As for Dornoch number 16, that is not an easy hole. It is easy to get into trouble with your drive, easy to embrace oblivion with your second and, even if you don't, still difficult to judge distance. If a hole is challenging, without being unfair/eccentric, I find it difficult to see where the word "weak" comes in, unless (see below) dissonance is somehow seen as weakness.
I agree it is dissonant in terms of style, but I also approve of that dissonance - it is one of the nicest tees to stand on on the course, and i also like the green perched on top of the world, aggressively flat etc.
Incidentally, if dissonance is weakness, then the first at Hoylake is a weak hole. I think not.