About this blue ....
This is just the stain coat, before the intensifying and finishing coats. I also use what I'd describe as a fast dabbing technique rather than the wipe or circular application shown in the vids. That seemed to bring out the colour and wood texture the best. I did two applications 24 hours apart.
That said, the back of the guitar will be a dark enamel spray blue. The DT blue has something to grip on the quilt maple veneer but doesn't really stain the smooth alder body or maple neck - Fretworn's 'faded denim' is a good description and I wanted a more intense colour for the headstock front and body rear. The neck itself will be a straight lacquer.