I think location and different osage has something to do with sapwood checking. I live in N/W Alabama, every stave I left the sapwood on checked just like the one I posted a picture of, that is over 25 years of osage cutting and probably 300 staves cut and saved.
As far as drawknives; the little ones aren't up to the task of serious wood removal. This is just me and I am sure someone will chime in about using the 8" Swedish drawknife for all their work and how well it works for them.
What I have found is whatever a person starts out with and uses will become their favorite drawknife. I started out with a huge debarking drawknife, I learned how to use it and can do very intricate work with it.
Here are my drawknives, the one on the top is my debarking drawknife, the one on the bottom is the Swedish one. the ones in the middle are flea market drawknives that work well but I like my debarker because of the extra weight, once I get it going I can take a lot of wood off quickly. I like my drawknives as sharp as I can get them.
The second drawknife down is a Greenlee, a really good quality drawknife that was pretty common back in the day, I gave $20 for it at fleamarket.
The third one down is a Pine Cone and a gift from a dieing friend. A HVAC guy who rehabs parolees came to work on my unit and brought one of his trainees, after they left I noticed things missing from my shop, the Pine Cone drawknife was one of the things that disappeared. As you can see it has a narrow blade, I found it was harder to remove wood with it because of the light blade.
The Swedish drawknife on the bottom is useless for heavy duty stuff, the blade is thin and flexes too much, the steel is good and it holds an edge well but I only use it for working around pin knots.
