You only get the output of a tile if a citizen in some city is working the tile. The city that is working the tile will get the output of the tile. The cottage line of improvements (cottage -> hamlet -> village -> town) will only grow to advanced stages when they are being worked in some city.
so there is no benefit to building a cottage outside the bfc, true it wont grow, but you don't even get the initial +1 either?
Outside the bfc, you only need roads to resources and to connect cities/civs, and the associated improvement for the resource? Cottages, windmills, workshops, plain mines, plain farms, etc, are only good inside the bfc?
-dana