Since we're in a rant mood.
The trouble I have with people like Stuart McGill, is that everything they say is treated like gospel by most internet bloggers. That's because most internet bloggers don't have the depth of knowlege in that specialised area to dispute what he says. Those that are able to dispute him, don't do it in public and it may be months or years before any valid criticism reaches the public, by then, it's in common practice. I just picked on McGill since he's the one that's come up with the curl-up but it could be anyone. I've been trying to find a critique of his bottom up kettlebell carry but I can't find anything except for the inevitable parrots.
Not that I want to nit pick - now proceeding to nitpick - but surely this would be trouble with internet bloggers and not McGill. He's largely just done his things and flew under the radar for a few decades. His internet presence is mostly due to other people talking about him. Also, his depth of knowledge on the spine is one reason I could never (or would need some very good reasoning) take an internet blogger or trainers opinion over his, particularly when having to deal with real spines/people. You can find opposing views from equally respected people, although they're getting less and less as people get a better understanding of what he's actually saying (Mark Comerford comes to mind for opposing the flexion argument).
Anyway, Drake, nice rant
I do disagree with planks being a fad, though. I think it's the same "ab" fad that's been doing on for decades, still based on the spot reduction myth. Just a new spin on an old fad.
Also, people will and do complain about planks causing back discomfort but, that's not because of the exercise, it's due to how it's performed. This is like saying squats will cause knee pain, DL's will cause back pain, Benching will cause shoulder pain, etc.
To me, planks are like touching your toes. You should just be able to do it. If you can't, you need to work on it. If you can, you only need to maintain the ability.