i see the role of an elected leadership as a supplement to the consensus process not a replacement. Basically they should usually be there to advise us but when deadlocks happen they would have the authority to decide whether or not a minority arguement is strong enough to block consensus - in any event a majority is always going to be the minimum to go forward with any change and a minority will still be able to block a short sighted change - at least long enough that they can be heard out and usually much longer. The difference is that the minority would no longer have what amounts to a guaranteed veto over any change - they would have to convince the community and/or the council why sometimig should be blocked. That gives a small minority the voice needed to steer us away from huge mistakes and to amend proposals through discussion and compromise but the days of a small cabal being able to hold the status quo without reasoned argument would be over. Consensus still wins.
Yes, blocking, by an small group, or even an individual (in other contexts) is fine IF they have a good argument, especially if it is obvious others in the discussion don't understand that argument yet. It should not result in sterile deadlocks though.
I continue to support that kind of council as a promising idea.
Fred