Thought I'd post a 'lessons learned' to close this off. After my last post I had one more session with the Dovo on the 8000, nothing heavy, just another 20 or 30 gentle laps. It just seemed to hit a sweet spot after that. Then I received my professionally honed King Cutter. It was very sharp, but by that time my Dovo is equally sharp and actually a bit smoother. So, the lessons learned are:
- getting a professionally honed straight is a great idea, to set a benchmark for your own efforts
- with the great info and support available on the site, I would say don't fear doing your own honing as well
- the advice to get a loupe was great as well - watching the coarse scratches get smoother confirmed I needed to keep going on the 8000

I'm now enjoying great SR shaves, alternating the two razors (when I'm not rushing off to work) and now have the confidence to keep both blades in top shape.

Thanks again for all the good pointers.