EY: The last pen and paper writing I did was constructing a master (and grand master and so on) keying structure for a small building. It involves writing hundreds of different key cuts (digits) in charts. It wore out my writing hand because it was just unrelenting. 10-20 pages of writing out different key combinations with 5 different cuts per key and at least 5 keys that will work in every lock it gets really tiresome.

I like using mechanical pencils because they are light.