Beiniek, i will also PM you privately about this to explain more about this and how best to handle it but i wanted to make a few public statements as i feel they will be of help to many others around here. Also, @Marko, i hope you do not take what i am about to say as a personal attack... that is not my intention. Please dont mistake my forwardness as trying to be an ass... that is not my intention at all.
Ok... here we go.
One of the first things I tell people when we talk about knives is this-
As a general rule, the more money you are spending on something, the more that will be required of you skill-wise, experience-wise, and technique-wise to be able to use and care for that effectively.
This is absolutely true when it comes to kitchen knives… and especially Japanese kitchen knives. That’s why there are beginner knives, like the yoshihiro, which are softer, easier to use, easier to sharpen, and easier to care for… and higher end knives like the Gesshin Hide, which are harder and require more skill to use effectively. If there wasn’t so much of a difference between the two, I would imagine that very few people in Japan would buy these kinds of knives… and for those who did, I would imagine they would see just as serious chipping issues as you are seeing here. However, that is not the case among professional chefs in Japan (and please understand that these knives are all intended for professional use).
Learning about how to sharpen and care for these knives is very important, and here are a few things that should have been done. First, when using knives like this, you need to do final sharpening (even if the knives come sharp out of the box). This includes uraoshi sharpening, which strengthens the blade. This also may include microbeveling the knife (either at the heel, or along the entire blade, based on your personal preference, technique, and what you plan on doing with the knife). If these techniques are not possible for you, I would recommend sticking to a beginner blade like the yoshihiro and practicing/learning until this makes sense and is possible.
Likewise, skill in using the knife is paramount. Chips like what you are showing here occur out of misuse more than anything else. Make sure you are using the knife correctly before anything else. It looks like you either cut bones in the wrong place, had an unsteady hand while doing so, and/or did so at the wrong angle. That, in combination with a lack of proper sharpening, could easily cause the problems you are seeing here.
Re-tempering a blade should never be on your list of things to do. Not only does it take away what makes the blade what it is, but it also shows a lot of arrogance thinking that the problem lies in the blade rather than your technique. I don’t think anyone here on these forums has the experience to say what an appropriate heat treatment is for knives like this… and I say this for the following reasons (I am including normal end users, vendors, knife makers, etc. in the following statements)-
*very few, if any, users here have serious and significant experience using these knives as intended in a professional environment
*very few, if any, users here have learned proper technique from qualified and experienced users of these knives
*most users experience with these knives is limited to just a couple of years (and when I say this, I mean significant experience where the knife is being used, cared for, and sharpened correctly)
*very few, if any users here have spent significant time with Japanese blade smiths learning about the construction, making, heat treatment, etc. involved in making these blades
*very few, if any users here have spent significant time with Japanese professional sharpeners learning about how these blades are sharpened and cared for
Most of us (myself included) began learning by just trying things out ourselves. We had some limited videos, books, and a ton or hearsay to go on, but that was about it. Its been more of a trial and error process than anything else and there has been a significant lack of understanding of why thing are they way they are, how things are intended to be used, and the subtle nuances therein. Until recently, I was in the same boat… I now have the opportunity to spend time with sharpeners, blacksmiths, and chefs in Japan and constantly use them as a resource when I have questions about why and/or how things are done.
To Bieneik, please feel free to use me as a resource as you go about fixing your knife and learning how to use it properly… that is exactly what I am here for. I’ll shoot you a PM in a bit.