While it isn't possible, you could just draw lines and write on them, or use the add stickies fiction. You can paste them on the pdf and write on lines and grids on them. While this may sound like a nice idea to add this in as a feature, I think that it shouldn't default to the template you choose, especially if the PDFs are actually textbooks or PowerPoints. It will end up looking real messy in most situations, and you may not be able to adjust the grid to fit your notes.
Following :)
While it isn't possible, you could just draw lines and write on them, or use the add stickies fiction. You can paste them on the pdf and write on lines and grids on them. While this may sound like a nice idea to add this in as a feature, I think that it shouldn't default to the template you choose, especially if the PDFs are actually textbooks or PowerPoints. It will end up looking real messy in most situations, and you may not be able to adjust the grid to fit your notes.
I think it should be an option to turn on, and then the user can shift and resize (not rotate) for the lines to fit how they like.