As I write this I have two of Mutsumi's River Jump Petty's from the NY Nigata fair in front of me, and a Tsukasa Flowing Clouds.
I believe that these are going to be superior to the original River Jumps. That's not to say that Tsukasa's knives won't be more desirable. If there's one thing I know about Japanese knife collectors, it's that they care more about how special and rare it is, than how it performs. However if we set aside collectability for a moment, I do think that over time, Mutsumi's will be a superior all around knife.
Of the knives I've owned from Tsukasa, the grinds are horrific. Like worst I've ever seen on any kitchen knife. I checked around to see if mine were uniquely bad and they definitely are not. Everybody I talked to agreed that these knives do not perform well. Very beautiful and special pieces of art, but not a world class performer. I had one buddy say that his was actually phenomenal and one of his best. Then he discovered the previous owner had it thinned. I have chatted with some of the retailers who order directly from Hinoura Hamono and they see the same things. Jon from JKI said that when they order them, they ask for him to make them as thinner and thinner every time because they are just so thick.
Now what I have heard about Mutsumi is that he seems much more interested in creating a really high performing kitchen knife. Looking at the ones in front of me, they are already noticeably thinner. Don't get me wrong, they aren't perfect, a little uneven on the grind, but they are definitely going in a better direction. With him obviously learning from his father, my guess is that all the things we love about the River Jump line will stay the same. And looking at these, other than the grinds, I would have believed that Tsukasa made these. The depth of the etch, colour of the ku and polish are all identical. With all that staying the same, I'm excited for geometry to be approached with a fresh set of youthful eyes. I think these are going to be amazing from what I'm looking at here.
I don't think it will be there right away, my understanding is that he's made and sold about five - six so far. But as he develops as a knifemaker, I think we're going to see really wonderful things from this line of knives.
