Yes, but if we want quick prototyping, we also want transformation of the prototype to something we'll use, which might need to be faster than our mockup. Take for example Arki: the wikitext parser was written easily using a quick prototype on raymyers' treeparse, but in actual use, the wikitext parser was too slow. Unfortunately, there's no easy way to transform the parser structure to faster techniques (such as state machines), without doing it by hand, which rather undermines the purpose of the quick prototype. By optimizing the underlying parser, however, the prototype was still useable, and by exposing a few more particular combinations (such as nil-returning sequences, for when we only care that a syntax exists or doesn't exist, not the individual charactes of the syntax), we can refine the prototype into something faster.
