I have added another tutorial for those following the New Watercolour Innovation.
It's called the bellycharge. By charging the belly of your brush with colour you can achieve some very smooth colour transitions.
Just to let you know that apart from the UK, there has been a lot of interest in this project from both Australia and the USA.
I'll add the "Rainbow Stroke Technique" just as soon as time allows. I need to take a few photos for that one.