Finally:

In reality, I must say, though, that Google analytics are the only measure that my bosses can go by to judge the success of a piece, and statistically, a lot of the audience moves on after 4 minutes, so the call has been to keep the tutorials down to 6 minutes, tops.
Serious users know that it takes more than 4 minutes to do a meaningful tutorial. What do they think, your teaching goldfish to draw Time lapse video's are fine for understanding that the author has great ability but don't teach anyone diddly-squat. I watched a time-lapse video of someone drawing a fantastic car in 3 minutes using only Paint, but I learnt nowt!

Also, I often revisit video tutorials (not just Xara Xones) and fast forward to the section I'm unclear on.