However, it is the method that can be at fault, not the notes themselves.
Notes written with a hard pencil, as he says, can horribly deface an endpaper, especially yellow glazed ones. However, if written intelligently and correctly, that is, lightly and with a 3B or 4B pencil in the right place, such notes can be erased if desired.
If left, they can add considerably to the book’s provenance for future owners.
Nigel Phillips
Hampshire