Do you think that the metal is soft and whatever you're using to sharpen with is getting clogged with metal more so than your other blades? Thus, making it almost impossible to get it sharp.
You may have to clean the rods/stones during the sharpening process in order to get it sharp.
We're accustomed to thinking every blade should take about the same effort to get it honed the way we like it. And normally that's the way it pans out.
The other issue I've ran into because I'm not consistent in free hand sharpening is getting off on the bevel. Most of the time I run a ceramic rod and strop to get a blade back to the sharpness I like. But, every so often, I use a guided system to straighten the edge back out so I don't screw up the edge.
From what I've experienced with a bad heat treat is the blade chipping when you get close to the apex of the edge.
Arguing with an idiot is like playing chess with a pigeon.
No matter how good you are, the bird is going to crap on the board and strut around like it won anyway