not bumping in to things requires a lookout, and a great deal of luck...and I would be concerned, and would step up the lookout....however, given the "virtual" nature of this URL siting and the nature of their research...i.e. no one has a "visual" on the patch, I most sincerely doubt the veracity of the danger or scariness.
I have read that hitting sleeping whales happens far more often than hitting partially submerged containers. And having seen quite a few containers, I am not sure there is anything that a sailor can truly do, to mitigate that risk...except lookout, or not go.
whilst there is some danger of hitting something substantial, the majority of the truly huge stuff from Japan has either sunk, become more waterlogged and sunk, or is light enough to float atop the water, and unless you are going much faster than most sailboats - will simply be pushed away by the bow wave.
I would be vigilant and watch my strainers so as to not have them clog and as I said I would watch...but scary??? Not.
What scares me more is shipping and power boats with either no one on the bridge, or the one low man who is there, is impaired or incompetent, and those ships who do not respond to the radios.
Night requires extra vigilance, look out, and more importantly luck...I would rather be lucky than good any day crossing the oceans.
