I was loading a fresh blade into my Ball End Old Type and noticed that the reflection of light off the bevel wasn't even after I had centered the blade and tightened it down. The blade was centered just fine, but as I looked edge-on straight into the teeth of the razor, I could see that the edge of the blade was making a slight frown. It was the same on both sides. The ends of the blade were curved down just a bit more than the center. I checked with a Bolzano, Astra SP, and Lab Blue and they all looked the same. Is this something that is usually seen in these Old types? Is it a result of them being designed for the old style of blade?