It's just harder for people for the reason that when you freestyle, you have a particular artistic target. You're lookin at a guy you can talk shit on and if you're lucky, respond to.
When you sit down with a pen and a pad, there isn't as much pressure, but the inspiration has to come from your head. You don't have a particular destination.
It's like when someone wants me to come up with a sig.. That usually is pretty simple. But if I sit down and want to just fuck around with the puter with no direction whatsoever, my graphics look like shit because i don't know what the fuck I'm trying to do in the first place, let alone what it's supposed to look like.