Well I guess it depends what most of your economy is powered by. If you have a lot of specialists then you will probably lose a lot of science switching to US. But if you have a lot of towns set up then you might as well get a hammer benefit out of them too. Hammers rock
I am curious to know how people use the buying part though, seems like it requires an awful lot of microing!
Hmm I'm sure this is good advice, but could you give some tips on why it is clearly better to go cottages in these areas versus specialists??
I can, but it'd probably start a CE vs SE war. I guess I should have specified that you want use GRASSLAND flatlands - plains are weak tiles for most of the game.
Anyway the long-term output of a cottage > specialist, ESPECIALLY when you take GPP out of the equation. What *usually* happens in games is that you'll wind up with cities that have a lot of food from a couple tiles and otherwise not stellar land (aka 2x seafood and a land food, but then plains or tundra for example), which is very well-configured to run specialists. This city will tend to overtake the others in terms of GPP production, eventually to the point of being the only city that makes any (especially true once you get national epic in there).
If you don't have any high food but otherwise bad sites, then you'll have to "force" it a little for GP's and just run specialists in your highest food city. Some players like a 2nd GP farm but I don't find it too necessary/particularly helpful usually.
Once GP are out of the question, a cottage that's grown even a little will tend to beat a specialist. For example, let's take an all grasslands example where you can either farm or cottage. If you farm, you'll need 2 farms to feed a specialist. If you cottage, each cottage will feed itself. Even before cottages grow, in this simplified scenario say you can have 3 pop. Even with the city tile factored in, you'd be running 2 farms/1 specialist (as is generally the case) for 3 BPT, 6 BPT in representation. 3 cottages are already worth 3 commerce (and that's a bit shaky to compare to direct beakers, but they're similar since you gold has to come from somewhere too!). As cottages grow, it becomes increasingly difficult for even high-food sites to beat specialists, although your typical high-food site will either be your GP farm or a production city (hills are not food neutral) in practice.
AGAIN, THAT'S WITHOUT CONSIDERING GPP. Great people can turn a game, especially if you bulb well and trade/get a shrine etc. This is why you definitely want to use specialists too, but generally cottages are only slightly weaker in the very short term and otherwise stronger once you have enough GP generation in other cities. They even overtake representation scientists after a while, although generally if you're putting up the pyramids you would want to short-term it with more specialists than normal. Civ IV is a complex game.
Hope this helps a bit.
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and of course the fact that while the food in this comparison is equal, the specialist city needs more pop. Good synergy for whipping and drafting, but then again those things are usually at their high point before biology.
