Hmmm!!! You've got the wheels turning now. As far as mounting something to the impression cylinder it can be done. As a matter of fact its routinely done when you score or perforate using litho score or litho perf. Think score or perf rules adhered to a sheet of mylar. A very precise introduction of the mylar sheet into the guides, both front and side, can along with a coating of spray adhesive onto the impression cylinder, adhere the mylar in pretty decent register to the impression cylinder. I see no reason why an embossing form couldn't be prepared and mounted in a similar manner, then using an expendable blanket mounted in its usual place to provide the backing for the required impression.
Here are the challenges as I see them. First would be, a duplicator style press would most likely lack the mechanical adjustability, to allow precise introduction of the embossing form through the presses infeed system. What I remember about these presses are that most of them infeed the sheet through a series shaft mounted overfeed infeed cams. This form of infeed would have pretty limited adjustability when trying to infeed a form of the required thickness. Secondly there would be a serious lack of working space when trying to mount the form. Remember, that once you've got the form in place on the impression cylinder, you would need to be able to access the impression cylinder grippers BEFORE the handoff between that set of impression cylinders and either the transfer grippers or the delivery grippers as the case may be. This access would be required so that you could (with a blade) cut off the very gripper of your adhesive mounted form BEFORE the gripper transfer takes place to avoid just tearing your freshly prepared and mounted form from the cylinder.
Then of course your next challenge would be a lack of adjustability of many duplicator style presses when it comes to position of infeed. Adjusting register of the emboss would be very challenging if even possible once the form is mounted. A blind emboss, with room to spare would be a limiting factor.
To summarize... I think I could do it if given the required time, and a press that offers the adjustability and hand access needed. I don't think a duplicator style press would offer either. And I don't believe it would be in the budget to supply the required time to wack out all the details unless of course your plan was to make this process a regular thing.
