DC, V cuts were such a pain in the rear, I just went to a squared up kerf by using the table saw. easy to slip a cut slat in to. Works best if you have a way to clamp it the same for each pass, but maybe 4 hacksaw blades bolted together on the ends would clean up the cut enough?
Anyway, other than that it's all been said EXCEPT..... I have had a lot of trouble with some woods cupping a lot more than others when using water based glues, even TB III. Thinner belly slats do it more, like a 3/8" thick belly lam would cup more than a 1/2" one. Goncalo alves was the worst for me, but other woods will do it, too.
I would check my fit, and be really happy. Then, when I wet the surfaces with sizing or applied glue, the whole slat would cup, turning the edges down and the glued side convex, bulging uip lengthwise in the middle. It's amazing how strongly this would defy the clamps, especially rubberbands, creating a tiny gap all along the edges between the backing and the core. Then I'd have to mess with adding more glue to the edges and reclamping here and there, or trapping the limbs to see if it would go away.
I started wetting both sides and waiting a few minutes to see what the wood was gonna do, then gluing when the surfaces were mostly dry.