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-If I recall correctly, the creator of the genesis block holds some kind of masterkey. As a result, you have to trust this person. Even if this key was held by a group, you still have to trust that particular group. In addition, you have to trust the program they run to create the Genesis block (the masterkey could be in there).
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This. The centralization of security makes it possibly even worse than Dash.
Well, in theory there is supposed to be a genesis creation event where the keys are generated and held by a dozen well known entities. The process is observed by people physically present and online via live video where the genesis block is created and all the keys are destroyed. Even if some of the keyholders are dishonest and somehow manage to make and keep a copy of their key it is useless without all of the other keys. As long as one person is honest or incapable of keeping a copy then the key is destroyed forever and the event never needs to be recreated.
With all that said, I'm rather dubious of the ability to pull it off and the trust that would need to be imbued by new participants as the currency gains more use. The point is that it is possible to setup in a manner where future trust isn't necessary, at least theoretically.