@stevejalim Yes - some Londoners use the F-bomb as punctuation!
There's a definitely a "polished" screencast experience - an obvious example that springs to mind is Jeffrey Way's Laravel/PHP screencasts on laracasts.com.
I can understand that without a script or clear goals you might end up with something akin to The Hobbit (the whole story and then some, but with some unrequired padding as well). It strikes me as odd that it would be compelling to watch (and learn from) somebody who uses the mouse a lot and doesn't use elementary keyboard shortcuts such as "highlight line", "delete line" or "wrap selection in a tag".
I could forgive the backtracking if they said something like "right, I can see that this code won't be dry and I've got a tight dependency, so let's rethink this and abstract X from Y - I'm going to be re-using X a lot later on".
I think a lot of people don't really understand what goes through a coder's mind (it's not like the movies after all!) and that sort of insight would be useful to people on the start of their journey.