https://youtu.be/DKJyvC2_JlY
In this test, I had my Longship swords sharpened to As Sharp As Possible. Their edges were tested by slicing through a deburring felt block without rolling its edge. Such a test was used on very delicate knives. Well, I like to put the metallurgy to the limits and see how well they did holding up against newspapers roll with twin bamboo strips core.

In the end, I figured I went too far. I have to switch to a tougher edge tester than deburring felt block, to produce a more robust edge for them. :P

https://youtu.be/4T0iCsxY_XA
Given a micro bevel at 40 degree with 8000 grit, the longship swords held against cutting twin bamboo strips cored newspapers rolls very well. The resistance had increased but the cuts still performed fine. So I guess that's a good edge.

https://youtu.be/RAl-lSKq57w
Using Longship Armoury 5160H Ex-blunt Dadao, micro beveled battle sharp edge to test cut a shin difficulty newspapers rolls with twin bamboo strips core, covered with linen bag.