If by "centralized 'mechanism'" you mean the fact that tonych control all 12 witnesses I'd say I don't think the mechanism of changing witnesses is somehow deactivate 'till the distribution is over.
I think it's in full blow validity and someone who present a very compelling argument to be one of the twelve witnesses could assume the role.
Now, tonych may have any number of reasons to be in this role, but one would be: the network had to start securely somewhere, and the other being: no one's showed up yet with the needed reputation and credibility.
Finally some voice of reason. I felt so lonely with my arguments among all "hodl, to the moon etc." mindless cheerleaders. Thanks for that. It would be nice to hear from tonych what is his plan (if any) for relinquishing control over witnesses and breaking down the current one man cartel. It's obvious that it's very early to talk about that but some plan needs to be outlined if the system is to be considered in the future something more than privately controlled currency by one man. It's so centralized at the moment that the wallet "decentralized value" slogan sounds like a joke.
I think I wasn't able to to express myself appropriately as I certainly wasn't advocating any urge for "tonych to relinquishing control over" anything, much less "breaking down the current one man cartel" in anyway.
In fact, I think the current situation is heath and expected for this stage of the project, and changing witnesses to be risk at the moment (I, for one, won't do this). Byteball need to grow much more so it can resist attacks as I think byteball's decentralized qualities will manifest themselves incrementally while it grows (I am currently learning and can not fully back this claim up, but I can sense witnesses may provide unheard levels of decentralization, much greater than many here acknowledge).
Besides, as far as I know, tonych can't do anything if economy decide to change some witness, apart from offering new version of the software (open source) which s0mehow enforce the witnesses he prefers. But then, he has to convince everyone to update to his version (admittedly very easy now as I think he, for the foreseen future, has much trust of the economy).
I guess, this puts me in the "mindless cheerleaders" category then

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