I'm curious and perhaps I'm overthinking this. I get the advantages of a shorter blade height, especially when I visualize (or in fact do) say peel an apple. Its hard to keep the edge on the roundish shape if the blade is too tall. In thinking about the Arete vs the Bushcrafter, it seems it was part of the original design goal, to improve slicing, food prep-ability. To, aren't campers and backpackers always thinking of ways to reduce weight? A minor point perhaps, but a lighter knife that does the same work is a plus?
When going from the Bushcrafter to the Arete, the blades are essentially the same length. The stock could be the same, say 1/8 or 5/32. But the height is different 1.1 for the Arete and 1.25 for the Bushcrafter. "All things being equal" (length and stock thickness), doesn't this 12% shorter blade height for the Arete makes it a stiffer blade? Doesn't it gain some advantage for those camp chores that involving twisting and prying? To though, staying with the same stock thickness, then that shorter blade means more metal behind the edge for the shorter bladed Arete, working against slicing ability?
Was there a sweet spot in the design of the Arete, where because it has a shorter blade height, one could go to thinner stock and not lose in blade stiffness for camp chores and not lose in above/behind the edge thickness for slicing ability as well as gain in the ability to skin an apple and carry less weight?
Am I being too theoretical?
I think there are a lot of things you are asking about blade geometry that may not be able to be answered here very well. But - I am going to give it a whack.
When you compare the BC to the Arete I think it is best to remember that just because both have a convex edge - it does not mean they have the same geometry. All good knife makers, Andy included, adjust their geometry to the tool, stock thickness, and task at hand. This means that with thinner stock, if the desired effect was to have a more robust edge - the grind would be thicker at the edge than if you wanted it for slicing work only.
As an example - compare an Arete in convex and an arete in Scandi. (This example is one of extremes - but will serve the point). You could have the thinnest convex grind (a near full height flat grind with a slight convex at the edge) and the shallowest Scandi grind with the most accute angle. This would show the difference in grind with the same stock.
So, given all of that - I don't think Andy grinds an Arete the same he does a BC because the blade heights are different. I think that he will take a little more off the Arete and allow it slice as easily as the BC without having the stock height behind it. In short, a Convex is not a straight line and so thinking of it as such can be erroneous.
With ALL of that said - if ALL else were equal and you were doing a full flat grind to the spine of the blade two blades with differing stock height would have differing angles. This means that your thoughts are headed in the right direction but may not apply here.
On a differing topic - let's talk about blade shape for a second.
Take the Ray Mears -Woodlore. Compare it to the Arete and then the Bushcrafter.
You see an evolving shape that has very different purposes. THe Woodlore is made primarily for wood carving and processing and would be pressed into service as a skinner or slicer (especially at 4 mill thick).
The Buscrafter is a slicer and has the belly to do the skinning - but would have to be pressed into service for much detailed wood carving.
The Arete is an attempt to be a compromise type of knife. A little belly - but not much. A spear point - but not too acute good at wood carving and slicing and can be used at skinning.
The Arete was my attempt at a knife that fit my needs in the woods. Basic wood processing, camp chores, slicing, and can be used to skin if needed.
In that, however, it is a lot like a Kephart type design. A compromise knife that is good at many things but not specialized to any.
I hope that helps for my thoughts on the process and I welcome anyone to tell me how wrong I really am.
Jason