Lol wut? It's the classic nodes being DOSed. Also, the whole network being full isn't even supposed to be a problem, according to Core. Prices will just rise? Correct?
This has been going on, on and off, since before Classic and XT and all the others were announced. Someone's been spending a fairly substantial amount in transaction fees to send spam transactions in order to "prove" that the block size needs to be increased and openly bragging about it.
Doesn't the action actually prove the point? At the very least, it's proof that the network is vulnerable to this kind of attack. Seeing as it has been ongoing, it can't be that expensive to do, since it isn't really going to result in a financial payoff for the attacker.