A method for analysis of a prototype graphical user interface (GUI) comprising the following steps: receiving, with a processor, a computer code representative of the prototype GUI, wherein the prototype GUI comprises GUI elements having known identities and known behavioral attributes; transforming the computer code into a description of visible sub-elements of the prototype GUI elements, wherein each sub-element has visual properties that would be visible to a user of the prototype GUI; grouping particular visible sub-elements into a perceived GUI element based only on the sub-elements' visual properties according to a grouping algorithm without regard to the known identity(ies) of the prototype GUI element(s) to which the particular sub-elements belong; and storing, in a non-transitory first memory store, the perceived GUI element.