I haven't read the book, so I can't comment specifically. Where the Barton's really shone initially was in the 2500+ variety. At first, they came semi-multiplier unlocked and could be overclocked to 3200+ specs with relative ease. At the time, that represented a significant savings. Eventually, they started locking their chips, but it's still not terribly difficult to crank the frontside bus on one to 200 and still get 3200+ specs - it's just not as significant as it once was. Furthermore, things pretty much topped out at 3200+, included Bartons sold at that speed (non-overclocked). There's not much headroom past that.
With the mobile Bartons, those are mulitplier unlocked, use less volts, and run cooler. Many people have gotten really decent overclocks on them and in the XP line, they've replaced the standard Barton's as the OCing chip of choice.
It's really old news nowadays, with the affordability of A64 and the availability of Winchesters (90nm). In AMD land, THOSE are the chips to get.
And FWIW, having owned both a Barton 2500+ (still do) and a 2.4C chip, I found much more satisfaction in overclocking the Northwood than I did the Barton.