Forwarding is NOT recommended as each invitation sent to a guest has a unique guest ID.
When a guest forwards the invitation they received to other people, they will be able to access the invitation as the guest that it was intended for, and any comments or replies made by additional guests will be under the name of the original guest who had forwarded the invitation.
If the host forwards the invitation to other people, it will ask them to sign in since it is a unique host ID for the host of the event.