I can definitely see the appeal of this - like you mentioned in your blog post, there's always worry that others will think you're stupid or something for not understanding something.

That having been said, I had a few questions/concerns:

- How would it work when there were specific gaps? It might be helpful if comments could be included to the instructor when the rating is provided. That would allow the teacher to reinforce those particular topics.

- How would you guarantee participation? If, for example, only people that don't understand the topic speak up, wouldn't that skew the data presented to the teacher?