but if you used a centralized server for your blog, wouldn't the date/time stamp of that server provide the same information as a mail server would?
In other words: wouldn't that file/database entry timestamp (ie: wordpress' time -- just an example/name of a blog not necessarily available at that time) serve the same purpose?
Yes — but if an evil person were running a blog like that, they could write posts about other people's inventions and put fake old dates on them. They could also fake the timestamps added by their mail server, but not the timestamps added by the mail servers of their subscribers. So the timestamp wouldn't have as much legal weight.
but if you used a centralized server for your blog, wouldn't the date/time stamp of that server provide the same information as a mail server would?
In other words: wouldn't that file/database entry timestamp (ie: wordpress' time -- just an example/name of a blog not necessarily available at that time) serve the same purpose?