I think that’s the shape I use for cleft grafts (curving tapered), just because I’m not all that good with a knife. 
For the scions below, I used mostly pruners…
From another thread, you mentioned:
I hadn’t considered that, but it seems like a good idea, so I tried it with one of my St. Julian rootstocks (two different peaches). I think it went OK, though I feel better about the cleft and bark grafts.
Logic I used in selecting the rootstocks:
1.) Thick and without much branching got 2 bark grafts of small scions
2.) Branched and medium thickness got a cleft graft of matching scion in each branch.
3.) The one in the bottom of the pic was branched, with a bunch of smallish junky branches, but not all that thick. I had some similar sized scions, so I used it for the double splice.
Actual graft:
