Not questioning the Allparts neck, I know you and others have had great luck with them. Always wondered why Gibson type tenons were necessary when a glued in Fender style neck fitted closely and glued properly should be just as reliable if you want a set neck.
No tenons on EBO or EB-3 necks...or NR TBirds if I'm not mistaken. I think using neck tenons might go back to building a solid body as if it were an acoustic. "That's the way we do it around here."
I'd also wondered about tenons. IMO what was necessary on an acoustic using hide glue which fractures on the glue line might not be needed on a solid body using aliphatic resin glue which makes the glue line stronger than the wood on either side.
I strung up the bass 4 hours after I glued it up. Wearing the proper safety equipment, of course. I think it will be OK.
I believe it's due to shear factors - the strongest points will be where it is glued at the "sides" so the more "vertical" contact points the better - Carlo will know where the grain of the wood can separate if under stress, so the choice of the body timber would need to be a more "vertical" grain to ensure this being minimised - the "Gibson" neck joint is more complex but provides greater vertical contact points so minimising these "shear" issues...
Does that sound reasonable...?
It does. Rock maple has no shear problem, neither does flat grain honduras so if the surfaces are both flat there shouldn't be a problem.
What's interesting to me on a 4 (or 6) bolt neck is that the 2 screws closest to the headstock are in tension, the others in compression and not really needed with a tight neck pocket. I only use 2 on my personal NR. No perceptible difference in tone or sustain from using all six bolts. But six looks serious.