1. A multimodal input system for use with an application program executed on a computing device, the system comprising: a dictation module configured to receive a recognized speech text input for insertion into a document that has keyboard focus, the recognized speech text input including text recognized from speech audio input by a speech recognition module; a scratchpad graphical user interface (GUI) configured to display the recognized speech text input, to receive keyboard input to effect edits in the recognized speech text input without changing a keyboard focus from the document in the application program, and to generate an edited speech input for insertion into the document; and a document-specific keyboard handler including a reflector configured to selectively reflect keyboard input, received from a foreground queue and bound for the document, to the scratchpad GUI for editing of the recognized speech text input, wherein the reflector includes a filter that is configured to programmatically filter the keyboard input while keyboard input is being reflected, and to refrain from reflecting exempted keyboard input that is determined to match a predetermined filter parameter, and instead pass the exempted keyboard input to the document.