this was a comment on the composition function. An open composition has offers and requests unmatched, to be potentially matched by other contracts joining later in the composition. Keeping these unmatched actions, however, has the disadvantage that the contract grows quickly. In a closed composition, these unmatched actions can be discarded, depending on the specific property to be enforced. This was a comment about a technique for keeping track of requests not matched, to be matched by future services, to consider them matched "on credit", and proceed to close the composition to reduce the size of the contract without losing information.