The eye is drawn to motion, which is another key problem with instant typing. I would bet you actually spend more total time & mental energy reading a sequence

The eye is drawn to motion, which is another key problem with instant typing. I would bet you actually spend more total time & mental energy reading a sequence of characters that keep disappearing and appearing than you do an IM conversation, where you can scan several (complete) lines in a second. You can also multi-task and multi-convo on IM without being rude, which is why it's so much better than a phone call for technical conversations w/ colleagues.