The Task Mapping Model (TMM) is a human-computer interaction technique that supports situational analyses to derive new design requirements from formative evaluation findings. While the TMM methodologies and formalisms are currently being developed and validated, this paper reports some informal first experiences and findings. Two developers who are presently working on independent non-trivial interfaces were asked to use TMM and comment on it. The developers found benefit in TM analyses, albeit in different ways, and their views were captured with an informal subjective post-analysis survey and reported here.