'The good steel' myth w/high end knives, fact or fiction?

Ok,
There has been several times now where I have encountered this 'gotta get to the good steel' comment relating to high end knives (shig, heiji, kato, etc) and issues with OOTB chipping after light use. I want to say this doesn't make any sense, so am putting it up for debate and am hoping Jon, Marko, anyone with a sh#t ton of experience in the matter can chime in.
I don't know anything really about knife making and bladesmithing so bear with me here.
A knife gets forged and then goes through heat treatment prior to grinding and final sharpening. At this point, whatever method is employed, a wheel and some stones, those 'sen' shaving things Kato-san and Iizuka-san use, whatever, there is metal removed from the edge and side of the knife to create the bevels. This steel that has been exposed, by the smith or sharpener, as the OOTB edge, how is it inferior to the stuff half a mm or less up where the user/owner first sharpens to?
If you watch Maksim's video of the Shigefusa visit you see them shaving the knives down, carefully, diligently, deliberately creating a very specific shape and then finishing them on whetstones. Does it make any sense that those guys would leave some kind of weak and inferior steel right at the edge??
And just to be totally clear, a sloppy OOTB sharpening job, like a burr doesn't count, that's not inferior steel, it's just not where it's supposed to be which is gone.
My assertion would be that most people inadvertently thicken the knife when they sharpen it because they are sharpening at a much higher angle than it was originally finished at. Therefore, it doesn't chip as much when they make mistakes in cutting.
I tried to make sense, but i'm not sure I hit the mark here guys, forgive my ignorant rambling.

Hello. After reading this post. I went out in the shop and was "grinding" a blade. Started thinking about this and here is my 2 cents.

You nailed the order in which most of the process is done. and I think that also helped to answers the question to some extent.

Due to the fact that the blade "profile" Is done and "set" Pre heat treat. That all the work that the maker does after heat treat often does not remove steel from the very edge... So actually when the maker adds the first actual edge. The steel hes removing would of had some amount of decarb/forging scale. etc. that has happened during the forging, heat treating, etc. This and other factors that could actually effect the quality of the steel right at the edge. Its only a few Thousandths of a inch at most. if ya dont over heat the steel etc. Yet thinking about it. I remove that decarb from everywhere else on a knife as I work on it post HT but the very edge... Then.. when I set my initial edge. I am generally only trying to remove as much steel as needed to create the cutting edge I want. Ideally one would get past that small area that may have questionable hardness due to the things I already mentioned. Yet I could see that the VERY apex of the cutting edge where the least material would of been removed. Could or would still have some of the decarbed steel, etc.

And then when a user reworks the edge a time or two.. They would get past the questionable apex and create a new edge thats actually better then the OOTB edge.

Thats about it in a nutshell. Until today I had never given this alot of thought. But due to what I just said. I will be modifying my process


Blessings
Randy

I've thought about this some as well and I think there are probably 4 different things that could occur that could cause the initial edge to be inferior to a deeper edge. First, it may be a perception thing due to a change in sharpening angle like you suggest.

Second, it could be like Randy said and the edge could have had some carbon loss during heat treatment called decarburization (note this happens with heat treatments done in a kiln and some in some forms of forges and does not apply to all heat treatment methods). Decarburized edges like could happen in a kiln heat treated blade would be less wear resistant or would fold much more likely and it would be unexpected that they would be more brittle or prone to chipping.

Third, it could be due to increased carbon content and increased brittleness/hardness due to carbon migration into the steel- carburization. Japanese forge heat treating is done in a oxygen-starved carbon-rich atmosphere that creates the conditions where carbon binds to the surface skin of the steel. This to me seems the most likely reason that initial edges are known to be chippy, at least from a metallurgical perspective. This of course would only apply to knives heat treated in charcoal forges as is done with some steels and in some shops, almost entirely in Japan (except Carter and maybe a few others).

Fourth, and I discovered this by having it happen to me on a knife that was reviewed on this forum a year or two ago- oog. The steel could get overheated during final polishing on the thinnest part of the edge and temper back a few points. This would cause a knife to not hold an edge as well for the first few sharpenings but gain hardness with later sharpenings, very much like having a decarburized edge. This happened to me because I was using a steel that tempers back relatively quickly at relatively low temperatures and there were no visible cues on the overheating. We mostly avoid that alloy now, not because it makes a bad knife when heat treated well, on the contrary, but because I can't test the hardness of an edge after the final polishing and can't be absolutely sure that the edge is at my ideal target hardness.

~Luke

Randy and Luke, thank you very much for your thoughtful and informed input!
very enlightening.

Just a thought, but I'm personally fine with this and would prefer it to the maker removing more steel than necessary. This way I get to go ahead and put my edge on the knife and have as much steel as possible to work with in the future. I also like a rather tall knife so that could be part of my rational.

Randy, Luke, great posts! Thank you so much

I often think about this, I get it in 1.2442 when used on the limit of hardness vs edge stability.
It can't be to do with decarb, that would have the opposite effect, Over heating is a different problem as well, the steel would be crumbly and not even take an edge if that was the cause. Its certainly to do with very high carbon levels and and optimised heat treatment with very little loss of carbon.
I believe it is from grinding as the edge becomes very thin it can flex, super high carbon steels at full hardness can still flex where steel is very thin at the edge, flex and return, not distort, they would chip rather than distort, that is the aim of this style of heat treatment. But continual flexing will make micro fractures in the hard steel. Think about an uber thin edge, vibrating from being ground and the forces of grinding, it will weaken and be prone to fracture on the thinnest part until material is more gently removed on the stones. I don't see this in tougher steels, 01 , blue 2, these would take more flex and ultimately distort on a microlevel rather than fracture,, only in very high carbon steels used with the minimal temper possible whilst achieving edge stability.
I have found myself putting larger microbevels on very hard Japanese knives though, if I'm cutting lots of hard crusty bread, or working around bones, but thats just knowing the limits of the steel and tuning for purpose. Or I should get a decent bread knife

My impression with a few knives (higher alloy and PM stainless), based on the depth and degree of the funkiness, was from fatigue or stresses like WillC described.

Thanks Will! Very informative.
Believe it or not, there's an 'artisan' knife shop around here that uses a picture of a finished knife held to a belt sander as the background for the sharpening services page on the website...

You could ask for the knife to come dull so you can sharpen the knife yourself.

Or have a lighter touch.

Or resharpen the knife out of the box to get rid of any initial worries.

Or go the French/German knife route.

Or contact the maker directly to complain when something happens and get an ear full of "...this is why I don't like to do business with Westerners...."

Or, and this is my personal favorite, give up cooking entirely and adapt a raw food lifestyle. Thus eliminating any need to worry about knife chipping.