For my opinion it really does matter on how the myth is arranged in the content. If it's still going to be 100 myth per run now you just need to run 5 more times per week I can seea hst of problems including this hypothetical scenario. ready?

So guy has been running his runs in a free company to try to keep up with the other guys, he's making cap on Sunday to "keep up with eh Jones". Now this guy still makes his 300 or 340 whatever by Sunday but he's now falling further behind. It's not a stretch of the imagination to think this guy might become frustrated over the course of a few weeks and finally give up and quit.

If the myth numbers for all the current and new content are adjusted to match this new weekly scale THEN it will simply mean faster progression thru endgame for everyone.