I can also assure you I speak faster than I type, and so it's not just your end that counts.
I'm also pretty sure I can say much fewer words with proper tone of voice to convey as much as 5x long email correctly, and a single word of your response and a look at your face as I speak will tell me more of what I should understand of your reaction than even the most elaborate written response...
Persuasion and discussion isn't about me laying out my point clearly in a tidy format though, right? It's about mind-sharing, interaction, sensitivity, etc.
Maybe we come from very different types of organizations? I have never, ever (!) in my 15+ year career been in a position where too many unprepared people forced me in any way to listen to their stupid / ill-prepared ideas....
[Edit] I'm also confused, how does someone coming up to talk to you forces you to write anything down?? (seriously I don't get that part :) )