Personally, I am a huge Jimmy Wofford fan and a supporter of more long format events. My trainer in south Texas competed long format and while she does not compete as much anymore, she is still a stickler for getting horses into long format shape, even if they're not going to be competing long format three days anymore. While doing some reading I came across a Jimmy Wofford article that I believe was published in Practical Horseman a few years ago, but not really remember having read it (I have the issue it's printed in somewhere) I went through it again and really thought about what he said. I really agree with a lot of points he makes about the reason rotational falls are becoming more of an issue.
The article in question can be found by clicking here.
He also mentions taking a look at the 2008 Grand National horse race, but the video provided was taken down so I did find a video of the 2009 race which you can find
If you don't have time to read the entire article I'll sum it up a bit for you. He starts off by talking a bit about a horse's initiative and watching the grand national steeple chase racing. These horses run about 4 miles, the average speed being around 800 mpm (meters per minute) and the largest steeplechase jump in the race being around 5-feet tall, no mean feat. Of course there are lots of rider falls, but he directs you to watch some of the riderless horses that continue on and jump several more jumps. The reason some people thought rotational falls were occuring more often is because "fast jumping makes for bad jumping". These steeplechase horses prove that wrong. Just because you're going fast doesn't mean you're going to jump poorly.
He continues to discuss a horse's initiative. When looking at eventing from it's inception as an Olympic sport (1912, Paris) to what it has become, we see that though we have lost the long format, the cross country hasn't really changed much, the dressage and show jumping portions have. For quite some time there was little to no collection asked for in a dressage test, and the show jumping obstacles were well within the horses' scope so it was less of an issue to really tell your horse to wait and adjust his own stride and movement because regardless of the speed you were at, as long as he or she was balanced the jump itself (height-wise, and even width-wise) was not as much of a challenge, so we weren't forced to (almost) over analyze every single approach and fence. Because we're now having to ask our horses for collection, something that makes a horse really give up a lot of its own control and initiative now we have horses that, instead of looking at a cross country fence and going at it on their own without a whole lot of communication from horse to rider, are constantly waiting for their rider to tell them what to do.
Though I wish it weren't so, we as riders are not infallible. We make mistakes. We get distracted, and sometimes we simply misjudge. When that happens our horses need to be able to bail us out. Nowadays when people look for a good event horse, a lot of them are looking for something with good movement to do well in dressage as well as looking for something that's responsive and adjustable in show jumping. People have started sacrificing certain traits (independence, maybe even something considered more fiesty or headstrong) for things like nice movement. While dressage is undoubtedly important, it can also be a detriment when you get to some of the upper levels. The key is to really make sure you're doing exercise that emphasize self carriage and initiative. For example, Jimmy Wofford mentions doing up and down bank combinations on a loose rein, gymnastics on a loose rein, really challenging your horse to "take ownership of the fence" without you having to tell them what to do.
I whole-heartedly agree with Wofford's assessment of the issues facing us, as eventers, today. While some think he's simple wary of change and longing for the old days, I see his point. Yes we had falls and such in the past, but it's so much more prevalent today! One of the first rider fatalities due to a rotational fall was in 1999, not very long before the eradication of the short format (2004, Athens, first short format Olympics), and since then we have seen an alarming increase in these types of falls. Something needs to give here and frankly while frangilble jumps are a good idea and a great safety precaution, I don't want to see people relying on them in the future with the mindset of "Well at least the cross country jumps have a better chance of breaking if I hit/fall on/run into them." (Since it's not for sure that hitting a frangible jump will cause it to collapse/break/etc. though they are trying to make it more of a guarantee.)