On Tue, 11 Jan 2011, Procházka Lukáš Ing. - Pontex s. r. o. wrote:

> Or is there another (non-layering or layer-merging) way?

You can also crop the pdf (\clip[mp=shape that you want to 
clip]{\externalfigure[...]}) and place that on paper using layers. That 
way, even if layers are toggled on a pdfviewer, the reader will see blank 
text (as opposed to old text).

But, I believe that clipping still inserts the whole pdf, so if someone 
really wanted, they can still extract out the original pdf. So this is not 
a failsafe way of hiding information; but is better than just adding a 
layer over the title.

Aditya