If it was my board, I would definitely use a clear p-tex candle so it looks a lot better. I only use black candles on black bases.
I like how he roughs up the surface of the gouge before dripping, although he should have done that before burning. You can also try using the torch to gently heat up the gouge prior to dripping as another way of encouraging adhesion.
A couple other tips:
- Let the p-tex cool all the way before scraping.
- Never breathe in p-tex or wax smoke. It is toxic and can make you sick. Proper ventilation is a must.