1. A method for differential dynamic content delivery, the method comprising: providing a session document for a presentation, wherein the session document includes a session grammar and a session structured document; receiving a prerecorded presentation control instruction; selecting from the session structured document a classified structural element in dependence upon the prerecorded presentation control instruction, in dependence upon user classifications of a user participant in the presentation, and in dependence upon a presentation history of the classified structural element; and presenting the selected structural element to the user.