I know it must be disconcerting to find ugly stria after using the 16K, but the real question is “how did it shave?”

Here’s a quote from Keith Johnson on scratch patterns left by a Vermio hone that might be appropriate here:

The scratch pattern off the Greek stone appear to be similar to what I get from a high-end 8k, or a regular 10k synthetic JIS. I have seen notably finer striations from other slates - my Ark, and Eschers. That is not indicative of much but it’s something to think about. Lunes leave the ugliest scratches, they’re horrible to look at actually, and the edges from those stones can be ridiculously keen. Coticules too – ugliest damn bevels but they can still be super smooth as well as very keen. So I don’t put much stock into striations and how they look most of the time.