Is it illegal to claim something under DMCA when it does not in fact represent a DMCA claim?
A. Nobody - NOBODY - is ever punished for violating.
B. The folks in question here think they have a colorable argument for why it really is DMCA. As linked from the OP, this is here [1]. (FWIW, I think it's silly)
[1] http://blockadblock.com/adblocking/is-adblock-plus-violating...