Predicting Stream Matching Behavior

(I am ignoring the Cross-reference and similar List manipulation components at the moment in order to focus on fundamental Grasshopper behavior.) When confronted with lists of unequal length, components exhibit different behaviors. “Dispatch” “recycles” (repeats) the “pattern” list, even if externally supplied, while “Add” exhibits the (traditional) “Longest List” behavior, padding out the short list by reusing the last item repeatedly.

Is there any way other than testing to anticipate the behavior one will see? Does “pattern” denote use of the repeating behavior?

Demo file: stream_matching_question.ghx (132.3 KB)