I have read somewhere that about 70% of street fights end up on the ground (not sure how you get an accurate bit of research on that though). As well, watching IFC and many other popular MMA that abound together with the explosive popularity of BJJ these days, it is clear that for those competitions that allow groundfighting a lot of fights end up there. Why? Is it that the stand-up styles lack decisive power? Is it that the groundfighters have a game so good it is no longer possible to deliver a knockout counter before they can shoot in?
Many styles seem to forego groundfighting...in particular Yoshinkan aikido (although Aikijujitsu styles such as Takeda ryu include it). Kali Majapahit is comprehensive and I see elements of groundfighting, while at the same time there is a strong emphasis on mobility. In that sense, the ground is used quickly, as an inescapable place where the opponent can no longer backup (ie. a "wall on the floor". It certainly is admirable to keep mobility, especially when faced with multiple attackers. But is such an approach really realistic?
two of my favorite reference materials here. If either of these guys ask for your wallet, give it to them quick. :-)
I have long admired groundfighting work by Gene Lebell and Mark Hatmaker both of whom I consider among the absolute best that can be found. While neither style seems to include deep philosophy (other than perhaps combat purism), technically and scientifically you have to respect the magic these guys have.
So where does that leave us? I suppose an Indian yogi would find little karmic value in the application of a good hammerlock for submission, I also find it hard to deny that groundfighting adds versatility to your fighting, the goal of which should be to feel comfortable in any environment and any condition.
I have more to study here, but in closing I think groundfighting skills remain practical and useful in our scope of training.
Stay Well Grounded!