UPDATE
Just a quick word about using the SP1K in a full progression for my Shi.Han, and raising mud like I do with the SP1500-2K-5K.
Raising mud, sharpening some:
Bit of finger mixing the resulting mud with water for some more polishing of the edge - just throwing concepts to the stone as I'm trying this, because I already knew I wouldn't be coming back to this stage for this stone...
As I willingly raised mud on this stone, I remembered I had tried this back when I was still relatively noob with stones - in the beginning of me discovering the use of mud with SP2K and 5K, like mid-summer 2020. I remembered why I never did it again until now, and why I had forgotten to remember: raising mud on that stone is rather painful for little amounts you get, it does give the stone some additional tactility, but at the cost of that mud having the stone dry way faster, and cut somewhat slower. It doesn't suit it enough neither that you'll want to lose yourself into sharpening on feeling. It's just adding a lot of pain to the use of a stone that is perhaps the most straightforward, simple, efficient stone I ever encountered.
First pic, you can see how little mud, and how it just wants to clump already, first sign of drying...
Second pic, dried out zones, a bit of clumped mud at places.
And despite the healthy amount of water given on the third pic...
Still drying out as I just finished what amounts to stropping more than sharpening, taking me like 1 minute.
TL;DR raising mud on SP1K, the deed of itself; will take as much time as completing a burr; managing the stone then with that mud, just the moves involved in what I did here... the stone would be clean and put to dry, next stone in prog already under sharpening, when using SP1K from clean.
Edge barely more lively, still not one I'd want to export into the kitchen... and anyway, it's just a given that SP1K is a natural born progression stone: it's goddamn fast and effective if the knife is dull, and edge will be usable, but no one serious about sharpening use this stone alone.
Shapton should slap a half 1K to a half 2K for a killer on the go combo knife reviver. Seems pointless for a combo grit prog, but with the intent of reviving a lot of different states of edges in say, a pro kitchen, and in aim of adding as little to the knife bag as possible, I'm guessing this combo would win over a LOT of folks.