To chunk up on a piece of information, use the questions: What is this an example of? What is the intention? The Milton Model, which uses vague or abstract language, is an example of chunking up.
To chunk down, use the questions: What is an example of this? What？Who？Where specifically? The Meta Model is an example of chunking down (who, what, where specifically) -- you ask your client questions to get more specific details.
Chunking up and down is a very useful tool in negotiations or mediation. Far too often in negotiations, we continue to explore solutions at a level of thought at which we do not agree. The key is to chunk up until you and the other person agree and then to chunk back down to the details only as fast as you both maintain agreement.
If we can use Chunking skillfully, that can help us to be an excellent communicator!