Not ragging on this piece in particular. It's just that people referring to this manual rarely add anything approaching guidance on how to expedite meetings and facilitate effective decisions. People shouldn't think of sabotage when something takes longer in a meeting, they should think of how the issue can be resolved quickly.
Tools I've found to resolve or prevent long discussions:
1. Ask every attendant their opinion in turn, so that people need not discover the other's take through discussion but have it explicit up-front. This is also very effective to break discussions where multiple people are constantly interrupting each other.
2. Make it clear when people talk about different things. "So you see technical issues #1, #2 while you see ethical issue #3?" Discuss the issues separately.
3. Keep the current best proposal for resolution visible for everybody, and change it as soon as anybody suggests amendments. Rarely split proposals into multiple variants, only if people favour clearly distinct options. Make the reservations explicit. "So you don't accept this resolution because it goes against (other decision)?"
And finally:
4. Accept that people can discover issues and change opinion during the discussion, this is an important function of a meeting after all. Make it explicit when it's happening though so everybody takes notice. If somebody keeps dredging up minor issues or matters already decided or discussed, ask them why they think it's relevant. Often it's enough to "add this to the minutes."