Well, if the videos had worked for me, the stats would have been 0.00001% higher 
I had issue for a long time where the vids didn’t play, so I never did them - 'Art of War' videos are not visible
And if many had similar issue, they may have given up on them, too.
I’m not a fan of the OP idea; I’d never use it. What would be better, imo, is to have a user-specified (in lobby) countdown timer for each age, and when the time runs out, all players on the map advance to the new age. It might simulate the world advancing in age, rather than just a civilization.
Not sure I’d ever play that way very much even, but I’d definitely do it more than the OP idea