That said, I predict cracks and early failure for the top. The author created something called "breadboard ends" (the left and the right side of the top writing surface have boards that run 90 degrees to the main boards of the top). Breadboard ends are a great technique - they keep the natural tendency of the left-to-right boards to cup (curl up in the short dimension) in check.
That said, there is one issue with breadboard ends: the long boards will shrink and grow in width with humidity changes over the seasons by 1/4" or more. Lumber only changes in width, not in length. So the breadboard ends will not accomodate the seasonal change...and something will give. Likely cracks will open up.
There are techniques to avoid this. Perhaps the author used some of them (only gluing the breadboard ends in the center, etc.), but if so I missed it.
Moral of the story:
* learning new things is great
* diving in is awesome
* sometimes trades do have semi-secret techniques evolved from dealing with the same damned issues over and over and over again.