I'm all for mandatory routes to keep riders off sections of road the organiser deems unfit to ride, but if they're being used as an alternative to infos, then swapping the freedom of an advisory route for them seems a poor trade. I've been on plenty of rides where different riders will choose their own route for their own reasons, no route is going to please them all and part of the pleasure is that you can make it what you want. I'll even make changes as I go depending on the weather, time of day, how I'm doing for time. Or even detour for a cafe, shop, something of interest or BCQ point. I rarely deviate from the route because another is quicker, but there's some events where that quicker route is at least as popular and it'd be a shame if there wasn't the choice.