City growth seems to have been broken some time recently.
On the 11.x branch... starting with a new map...
either letting cities grow "naturally", or using the "+100" city growth button, results in growth along the inter-city roads, rather than growth within city limits. This results in long vines of growth rather than the clusters we formerly got.
Is this on purpose?
There is a parameter (from Standard) that affects the extent to which cities will grow outwards along existing roads or stay within their areas.
Since I am planning to change the way in which city growth works at a somewhat fundamental level for the major release after next, there does not seem to be a great point in fine tuning this now.