He provides a list of why whiteboards work:
"Whiteboards are big enough for everybody to see.
Whiteboards make you want to fill the space, and therefore expand and branch your thoughts.
Whiteboards inspire you to keep writing, to keep pushing on what's in your head, because it feels awesome to swing your arms that widely.
Whiteboards feel less like you're committing to an idea than throwing it out for consideration.
Whiteboards are nearly impossible to lose inside your backpack."This latter point, was until recently, my major problem: I did not have a camera with me all the time to capture each session. But now that I have a cell phone, that is solved: