After ripping up my thumb with that nasty kickback I finally got to the shop today. I still had one my cut to make using the jig that bit me. I was very reluctant but I had to make more cut so that that parts would mate up.
Once it was done I felt a little vindication and a lot of relief!
Then I moved on to a new jig. I had decided I was going to just cut out the knots in the middle of these long pieces on the RAS. Then I would just build a jig to sit on the RAS table and cut the actual scarf. After a lot of looking and trying stuff I came back to the fact the table saw is the best tool for this operation. One cut and your done. No new setups. No double cuts. No fuss no muss.
I gave in and built a new jig that I think is better than the sled. No chance of pulling a part back into the blade. The off cut just falls on the table where I can see it. The left handedness of this jig put me out of the line of fire. And I added some walnut handles I had laying around I never used and these keep my hands well away from the blade of the 'line of fire'.
Made a couple of cuts and I like it, don't trust it yet but it seems to work OK.
Still looking for better clamping method but being so close to the blade it's hard to clamp the parts.