One of my favorite YouTubers just released a video that chronicles the discovery and repair of the near-catastrophic failure of the aluminum frame on his Trillium Outback. I found it interesting to watch....especially since several other manufacturers either already use aluminum frames or (in ETI's case) have plans to do so .
This particular frame was retrofitted by Outback in place of the original steel version a couple of years ago.
Those who follow Slim's travels will know that he doesn't baby his trailer. However, Based on his channel content, I've never seen him do anything extreme enough to warrant this kind of failure. I doubt his rig weighs any more than 2000lbs. He doesn't use a WDH either.
The video suggests that excessive tongue weight might have played a factor, though I'm not sure if that's the case.....