I think this might be Jackies video, sure sounds like him anyway. Turns out I was on the right track thinning the blade. It's a good video and worth watching!
https://m.youtube.com/watch?v=prUTUd9trmA
Why it's so easy to do a beaver.
https://m.youtube.com/watch?v=NYQ-0BvAO_o
Thanks Spruce for the lead on those videos, I hadn't seen them, very helpful.
It looks like I'm back to square one with my knife.