Ask PG: Implementing checkboxes to improve comment quality

I'm curious about how the overall quality of comments would be affected if you put 3 checkboxes, laid horizontally under the comment box, that must all be checked before submitting a comment. They'd be something like "My comment is: -civil -well thought-out -sincere". In addition to the psychology at play, maybe just having to check 3 boxes would curb some of the more trollish and emotional comments. Laying them out horizontally would also require a bit more focus than having them stacked vertically.

Of course, this might not work at all.