So this would put the control in moderators' hands. I don't think that's an improvement at all.
the control is already in the moderators hand, if someone can ban accounts then it's not the best argument to say that putting them in control is not an improvement. since we can not have voting , elections or anything of that kind then moderators must have control. in fact someone with the power to ban accounts can ban a DT member right now for no reason so we are not actually giving the mods any sort of extra power. and even if we were to assume so, i personally rather see a moderated trust system than a random trust system, at that point the majority of the feedback will make sense to the majority of people.
Even assuming the enforcement can be super fair, it's still not a benefit to have the trust system conform to a rigid set of rules. The variety of opinions is part of what makes it usable. For example when The Pharmacist started tagging account traders I added him to my trust list because I wanted to see which users are account traders. That was before he was in DT. It looks like your suggestion would take away that flexibility if everyone is allowed to tag only for trades. It would also remove the ability to warn about ICO scams etc.
"The variety of opinions" is the root of the problem. you can not have a "The variety of opinions" in a trust system. especially that DT member's tag is the THIN LINE between a usable account and a non-usable account[1].
[1] -almost every signature campaign states that if you have a negative trust you can't join.
-the majority of people will not be willing to trade with someone who has negative trust from a DT member
I mean look at the contradiction of DT feedbacks on the same members, this would have not happen if the rules are there.
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DT trust needs strict set of guidelines.
So does merit.
I do not agree with the merit part, it will be impossible to monitor , plus i totally disagree with your theory of that the top merited people got their merits from each other "at least this is what i understood" even if that was to be true, this can simply be due to the fact they actually deserved it? also if you look at most DT members merit score, is just an average, except for a few like suchmoon whom i am totally against his/her way of describing the use of the trust system, i honestly think he/she deserves all the merit it due to the quality of his/her posts.
so please don't take this off-topic. merits are a whole different thing. we are talking only about trust system only here.