From what I've read William and Catherine attended this event (the blue print dress medical meeting) privately to learn about the work being done. Thus no press and only what appear to be snaps from a cell phone of Catherine and none of William. We don't know the nature of the meeting, but we can assume that neither Catherine or William were making a presentation. I don't know what type of meetings you frequent, but IME her dress is entirely appropriate for a daytime meeting in a professional office environment and much like I would see in less formal working business meetings and among the audience at conferences or presentations - particularly if the weather is warm. To criticize her choice of dress for this private meeting w/out even knowing the exact nature of the event or seeing how other attendees (if any) dressed seems to me to demonstrates a bias against the Duchess rather than being some kind of opinion or observation based on evidence.