So a bit more on this...
Back in the day, Fender used to call the two board types "slab" and "veneer" because they literally were... a radiused slab, and a thinner piece of rosewood that was bent over a radiused neck face.
But the veneer deal is not what Jimmy does. He told me he actually shapes the bottom of the board, so it's really more of a "cap", where the wood is "fitted" to the neck... not bent to fit the neck. This as opposed to a veneer, where the wood is bent to fit the neck. Again, I can't recall if that's the exact word he used tho... maybe Kirk, Jason, or Yohan can chime in on that.
I did a little reading on this and the tonal result should be as expected... the neck wood plays more of a role in the tone.
The big difference here is, I'm guessing Fender simply did it to save money, and didn't really care about wood grain distortion from bending. I take Jimmy's process to mean he wants the wood grain to be intact... identical to the grain in the blank he started with... when installed.
I think this is a really cool option, but I think my personal preference would still be the slab. Not because that's what I already have, but more because if I want a rosewood board, I really want as much participation from that as possible. That is obviously not going to be everybody's choice, but it would be mine. I can easily see, on the other hand, where someone wanted some influence from the rosewood, but still wanted as much maple participation as possible, and would find this a great option. Also, if you're trying to be period correct to a specific period, this is just one more way Jimmy offers a way to get there.
FYI.