Stephen C Brophy - Niice video! Much better seeing things from the inside.
Gemma - I was like you. I still take too long, but to a lesser extent now. After taking advice on technique, I did what Helen is suggesting and I am now spending less and less time on my own house, and my customer's houses, with results that are just as satisfactory. Getting quicker all the time now.
I did have a small number of windows where one, or two, panes always required more attention - but, over time, even they became less problematical.
Mike