Your original premise, as I understood it, was to send a message to a group of people and possibly have people comment on it. With your new proposal, the recipients would not be able to see each other's responses.

It also will shift the burden solely to you to answer any questions or provide clarification. If recipients were able to see other recipient responses, they could do some of the work for you.

But, for all the use cases I can think of with regards to sending messages to multiple recipients, I cannot really think of a good reason to prevent recipients from seeing other recipient responses barring some communication of a personal nature.