I have continued to research source of the shake associated with screens mounted to headlight bucket brackets. My speculations do not apply to screens that use handlebar stays, which are more rigid, but just not what I like personally.
Checking the headlight parts diagrams that can be seen on
http://www.babbittsonline.com, I found that there is a difference between the steel rod frame the headlight bracket brackets bolt to for 2013-2016 CBs, compared to 2017-2018 CBs. The 2013-2016 rod frame is "H" shaped, with the two upper legs rubber mounted into the top fork bridge, and the same for the two lower legs into the lower fork bridge. I am guessing the "H" shape would be less prone to twist flex, and movement would probably be more from the rubber bushings. I am also guessing that the rubber mounting is to reduce vibration of the halogen headlight bulb.
By comparison, the 2017-2018 steel rod headlight support frame is "Y" shaped, with the two upper legs rubber mounted into the top fork bridge, and the single lower leg rubber mounted into the lower fork bridge. Since 2017-2018 uses an LED headlamp, and I am not aware the LED lights are particularly fragile or vulnerable to vibration, I am wondering if rubber mounting was necessary? In any event, it would seem to me that the "Y" shape would be less rigid than the "H" shape, and more prone to twist flex. That, combined with rubber bushings, I think would make screen shake more obvious for 2017-2018 CBs, than 2013-2016 CBs.
As I previously posted, I was not aware of shake associated with the beautiful and very popular Road Comet, until I read this post:
http://cb1100forum.com/forum/showthread....light=puig . It would be very interesting if guitar gord, and other members could post a short Go Pro, or similar video clip of what kind of shake they are seeing, or maybe a link to a Youtube clip. This would be very informative, whether it is the Road Comet, Dart, or any other screen.
The only solution other than adding handlebar stays that I can think of would be fork tube mounted brackets, something like this set on Samurider:
https://www.samurider.com/?p=20073 . I imagine Mr. T could say whether or not it would work with Road Comet for 2013-2016. It would not work for any of the Dart, as the Dart brackets move the headlight further forward than stock to achieve correct rearward angle on the screen.
Although it has not resulted in a solution ( yet ), I have trade emails about this topic with Dart, and have found them to be every bit as professional, responsive, and cordial as Mr. T with Samurider. As I like the clean OEM look of Dart, I will probably end up going with Dart regardless of any shake that might be present. I hope my speculations will be helpful at best, thought provoking at the least.