@John_Brock and @theoutside just as an fyi, I would venture to guess that these symptoms are not directly tied to display. When stuttering occurs at specifc moments like beginning of a command or the selected items change this is commonly some other part of Rhino’s user interface doing too much work to update it’s state based on the changes that just occurred. Hopefully we’ll be able to get a file that repeats the issue.
Now that I’ve written this Murphy’s Law will make it that this really is a display issue.