If he did the cooking and you did not restrict the use of the knife to only cooking, no fraud occurred and there is no broken contract. Lets say after he is done cooking, a home invasion occurs and he successfully defends his family with your knife. Again, as long as he did what he said he was going to do with the knife (say to cook some food for you) and delivered both food and knife to you as agreed, there is no violation of contract. If you want to make sure that the only thing he uses the knife for is the cooking, you had better spell that out (for instance, kosher rules governing what the knife touches).
Some restrictions are implicit. The typical example is that of the boat ride. If a friend of yours offers you a boat ride, and you agree, it is implicit that he must bring you back to land. He cannot demand you to leave his property on the middle of the ocean.
Miners on eligius have, for sure, agreed to mine BTC on the pool in return for the payments they receive. It is not clear at all that they have agreed on using their mining power to attack innocent projects. And even if they had, that would only make them accomplices of Luke-Jr unfair act.
The coin was released with merged mining and the largest pool doing merged mining was not acting to appreciate the currencies value. That is a structural flaw in the launch of the coin.
So allowing merged mining is the "deep flaw" to you? Really?
Such a feature would only be considered a flaw if you assume that
- There are rogue, ill-intended big pool operators out there.
- The miners of such rogue pool operator would support an attack on an infant technology that has done no harm.
Honestly, I wouldn't call that a "deep flaw" since, before this shameful event, I would not take such hypothesis as something to worry about, particular the second one. I guess I still had more faith in mankind than I should have, it seems.
Even worse than Luke-Jr promoting such attack is the fact that he's apparently, so far, "getting away with murderer". Depressive. It's as if lots of miners would collude with deepbit to reach >50% and start double-spending to their profit.