I don’t particularly write for an online audience, but netsurfers I speak a truth; short » long!
Yeah, obviously (duh), but the average estimated attention span online clocks in just under a goldfish (9 seconds) or maybe more! I’ve only fully realized this by happenstance in a sorta offline–ish short/long blog experiment, but it blows my mind because my ability to focus is typically 2~4 hours.