That idea is fine if I'm not already cruising snippets. In this case I was and was forced to return to 'Home' to find the link to post a snippet.
It makes just as much sense to expect to be able to post content when viewing the content as it does to have a link to it from home.
I think doing both is practical and convenient.
The idea is that you post everything from home or your profile for the sake of consistency. Would you have not thought to post from home?