Upload & Sell: Off
Jim's statements are exactly why Dave did this. His reasons for going with the speedlight kits are factors such as weight, the ability to work at any shutter speed, as well as pretty much any exposure value. Cost was one drawback, but given that he already had a list of clients he could use this with, the cost over time wasn't too bad.
Sure you can strobe out a place, but unless you do it right, there are ghosting issues. Overpowering the sun? Yes, but what are your exposure value limitations. . . such as having to shoot at very small apertures (f/8-f/16, etc) in order to work with your limited shutter speeds. Oh, and how much portable power do you need for all this.
The only other way to do anything similar to this is to use a CCD camera, because of their electronic control over shutter speed. The drawback to this is that CCD technology has been pretty stagnant, limiting you to older technology, which brings about its own challenges (limited megapixels, less dynamic range, low ISO noise tolerance, crappy LCD tech for reviewing images quickly, crappier battery tech, etc)
Dave Black is an amazing photographer, and given his experience, he's thought this out, and to him, the value of doing this far outweighed the negative aspects. Anyone who's had to lug their own gear and install their own strobes and remotes would agree that factors such as weight and size play a role in the logistics of a shoot.
When I shot with a D40 against the sun, I used an SB800 with a Quantum Turbo SC. I had access to Elinchroms and other strobes, but then I would have had to consider weight (Vagabonds or similar all weigh 20lb or so), vs cost (Quadra Ranger comes in at well over 1k, and isn't necessary for anything else I do, though I do want one), vs effectiveness (all other setups would have given me more leeway, but my goal wasn't to tackle the sun, simply to compress the dynamic range of my scenes, so why did I need a 400-600ws pack or head?).
Just my thoughts.