But you might want to compose various methods on the server in order to filter, just like you might want to compose various methods on the server in order to transform. Why is `collection.map(server.lookupByInternalizedId)` a special case that doesn't require `server.lookupCollectionByInternalizedId(collection)`, but `collection.filter(server.isOperationSensibleForATuesday)` is a bridge too far and for that you need `server.areOperationsSensibleForATuesday(collection)`?