You block someone when you don't want to see their stuff anymore. It shouldn't have any effect on whether they can see or interact with your comments and the rest of the community. If they are block-worthy, other users can block them too.
You shouldn't really care about what they have to say after you've blocked them. If others see you never engaging with them, they should get a clear picture that you don't deem a reply necessary. If you're really concerned with rebutting everything they have to write about you or your ideas, then the correct course of behavior is not to block them.
Pamasich