In a) case, if somebody expresses me he/she feels annoyed, I guess I would just have a talk to better understand the situation (his/her understanding of the role i'm speaking from, or what makes him feeling unconfortable). But I would keep reminding people. maybe using a checklist item too.
In b) case, yes if there are no domain or other rule about it you can do it. Nevertheless, depending on the situation (maturity of the members in Holacracy), I would pay attention to let space for the others. And maybe I would use other pathways in the first place :
- go to talk to the role filler (you wrotte : We have a role “content magician” whose accountability it is to set dates for when to publish articles for the foreseeable future and to ask people to add their names to the list) and pitch him first. Asking him about what action he decided to express the accountability, or asking him to take one.
- at some points, I would let people do their own experiences. Maybe there is not a big risk in terms of image, or activity, in the case you described (he says he would have done the same one week after). And I would ask myself if there is a risk to let the role filler do as he wants, even if I'm convinced I would have done it better. That's something I experienced in a circle, it was often hard for me, but a reasonable price to let some roles and concentrate my energy where I wanted. And the question "is there a risk if I let things going that way, even if I find it's not good ?" helped me a lot to control myself.
- If you're the Lead Link of the circle where the role "content magician" is embedded, you can give to the role filler feedback and have a conversation about it as Lead Link.
Those 3 ideas in order to help him to energize maybe better the role, instead of acting in a way that avoid him to energize it better.
Hope that helps, have a good day !