As a moderator on Raspberry Pi Stack Exchange site a fair amount of my time is spent commenting on posts by new users that they should visit the Tour page to get a better understanding of how the site works.
Reasons for this most commonly include a question being posted in the answer section or a question is posted that is too broad or off-topic. It gets to be quite tiresome to post the same comment along the lines of:
Hello and welcome to the site. Your question is too broad for the Q&A format of the site. I would recommend you take the Tour to find out how the site works.
My thought is some of this hassle could be cut out if a new user had to visit the Tour page before being able to post. A counter argument to that would be they'll simply scroll quickly through to the bottom of the page without reading anything. An alternative solution could be you have to watch a short 30 second video explaining how a Stack Exchange site works before being allowed post anything.
I prefer the second option because people are lazy and watching a 30 second video isn't as much hassle. Of course there will be people who won't pay attention, but that solution might see a higher success rate over forcing someone to read a Tour page.
In either solution the Tour page would still exist in its current format. Also if you join another Stack Exchange site, and you already have 200 rep on a site, you wouldn't have to look through the Tour page/watch a video.
I'm not saying this is going to completely eliminate the problem that sites like Raspberry Pi Stack Exchange face where there is a large proportion of new users compared to active high rep users. But it could help to reduce the issue.
