Taking myself formally out of the committee means you don't need to wait on my half-baked votes.
Please, Imp, as if any of my votes have even come within ten feet of the oven!!!
In my view, all discussion of all ideas is good, so long as the train does not get de-railed. But I don't think it's the obligation of the person asking a question, or making a point, for ensuring that the train stays on track, but for the committee in general to press on. So that if a point that's already been decided is re-raised, the re-raising of the point shouldn't be a problem, so long as we don't let that re-raising stop the progress.
So, what I would expect if I raise a point that's already been settled, someone would simply let me know that this is the case and I wouldn't have an expectation that my raising the issue would suddenly cause it to be re-opened. In that case, I just wasn't there in time -- for other issues, I may be there in time to provide input. I don't think we need to have every single person on the committee fully up to speed on every facet of every issue -- heck, US voters aren't, members of Congress certainly are not and (as I'm about to experience this week as my organization holds its quarterly board meeting) corporate board members are not.