If you believe that time is a stream with many branches, then many of those branches will have "similar events." These events, if large enough, will send out energy in all directions.
Just using a hypothetical example: Someone plants a nuke in New York City. With 7 million people there, there are 7 million different futures. They all go along their pathways.
If the bomb goes off, that will affect 7 million timelines and send out 7 million shockwaves forward and backwards on the timeline. That amount of energy (plus everyone watching on TV. around the world) would have a deep impact.
Someone tapping into that energy would be able to get a "picture" made of bits and pieces of the whole. It would create a mosaic type image. It is my contention that is why so few of these things present a "clear" picture.
Add on top of it that WHEN something major happens, not everyone realizes what is happening at the time. Our memory of 9/11--if you were to draw it--would be more from the images AFTER the event, than from memories of the event. Therefore, they do not emit the same "energy." This confusion--people saying, "What the hell is happening to me" would add to the fogginess of any interpretation of the "viewer."
Finally, the viewer is seeing everything through their prism and experience. I understand they are trained to dismiss those things and be as objective as possible. I would suggest that is not 100% possible. There are sites and smells that once you see and smell them, you will NEVER dismiss them. The smell of burning hair--if you have ever smelled it, it is not something you could effectively dismiss.
So, yes, I think we all agree on the "many futures" lines, but it explains more than it detracts.