Jason - the one this weekend was in a different spot than the previous. There needs to be something there to stop a bike from continuing (i.e. berm) though, so just taking them out won't work; I've been wondering the same thing as you though. Take Bob's crash for example - without the berm, he'd have taken out the fence between the track and the access road, though with it you end up launching any rider or bike that impacts it.

IMO about the only thing one could do there would be to lay down a nice bed of gravel trap to at least slow people down, since you can't very well airfence a pile of dirt. I'm sure there are issues with having gravel too, and maybe there are better ideas, but it seems like the lowest maintenance and possibly cheapest way of adding some speed control to those areas.

I doubt there is room to do what MMP does, but their traps are started with some hardpack to allow someone to use the brakes before hitting the deep stuff - it's a pretty cool idea.