I've had this come up a few times over the last few weeks. Every time I've done the command the emerge has failed somewhere along the way.
Is this adding some value that I don't understand? What does it do that using revdep-rebuild doesn't? Granted, I have no way of knowing whether revdep-rebuild would have failed or not failed so maybe it's an issue with the quality of what's in portage these days but I'm not grasping why things are getting to be more work for fewer good results. Thanks, Mark