It's not "spray and pray" or FPS that make the 1D series cameras better at capturing action, its a completely SUPERIOR auto focus system that Canon has yet to trickle down to the XXD or 5D cameras at this point. Focusing speed and accuracy is going to be greatly improved with a move to a 1-series, for sure. No question about it.
There may be people that are certainly pleased with how their XXD's perform, but that does not mean the 1-series are not overall a better AF product. The 1-series cameras have separate processors set aside just for the AF system alone. Let alone the customization that is available with regards to the components of the focusing system on a 1D.
Rob Galbraith broached the subject in his review of the 1D Mk III of whether or not a 40D would be an acceptable replacement for sports shooting for a 1D and here are some his comments - keep in mind this is regarding a 40D....probably a faster focusing camera than the 30D....
"With an EF 300mm f/2.8L IS or EF 500mm f/4L IS lens attached, the EOS 40D produces an unacceptably low percentage of properly focused or even usably focused frames of track events, soccer, rugby, football and basketball in our testing. Even as a secondary body - for instance, acting as the short telephoto camera when the action comes too close for a long lens - the camera's AF falls short. At best, we've seen it get about half the photos in a sequence in focus, while for grab-and-shoot photography it has missed the focus on more frames than it has gotten right."
or
"We don't plan on doing a full-blown analysis of this camera's AF capabilities. But, we have done more than enough shooting, using cameras and lenses that were calibrated and otherwise operating properly, to say that the EOS 40D is not a viable sports camera. A midrange digital SLR with a midrange price tag probably can't be expected to offer the same autofocus performance as the company's best. Even taking that into account, though, the 40D doesn't fare well. It's not that it can't do the job at the level of a more expensive camera, it's that it can't do the job really at all."