The question is (suspence):

what happens when a city radius is cramped by tiles controlled by other cities? Will I still need the same number of workers to gather 100% of the resources in the radius? I hope not, because this would be an efficiency disaster later in the game...
For example, if 3 tiles of the second ring of city expansion are cut because they are used by a nearby city, will I need 3 less workers to gather 100% of the resources of the radius? (remember, 3 tiles less are cutting painfully the total amount of resources in the radius).
If so, what will happens of these 3 useless guys?
Will they be specialists? Will they be able to gather resources from the next expansion radius after the relative expansion eventually takes place?

Example: a full second ring is 12 squares. So each citizen that you grow while in that ring provides ~8.33% of the total resouces in that ring. Average unimproved land territories have a total of 25 resouces (not desert and jungle or frozen). Total resouces in that ring are 12*25 = 300. The result is that each citizen in that second ring adds 25 resources. If you have one simple farm, you have 310 resources in that ring, so each citizen adds about 26 resources.

What if the ring is cramped? Say you lost one side - now the ring is only 9 squares, for a total of 9*25=225 resources. I think it still takes 12 citizens to grow to the next level, instead of merely 9. Each citizen (8.33% of the ring) now only gets you ~18.5 resources. It may be more efficient to use specialists if your ring is cramped. This is especially true for a large outer ring. You might end up with only 40% of a ring - each citizen generating a base of 10 resources. That sucks.

Questions:
1. If you reduce the number of workers (add specialists), does the area worked collapse? I.e. if your city grows to 19 and expands to the third ring, but you then make a specialist, does the city reduce back to only the second ring? Or is that third ring now claimed and thus inaccessible to other cities?

Note that a size 1 city gets two free "pops" for purposes of working the inner ring. I.e. in addition to the city square itself, and the city bonus, a size 1 city gets 3/8 of the first ring of 8 squares. Thus, a size 6 city gets 8/8, or the entire ring, and size 7 goes to the next ring.

A city with a cramped ring is SCREWED.

If you lose half the 2d ring of 12 squares, each pop that works that ring still gets 1/12th the resources from it. You get 12 people on 6 squares. At that point, start making specialists! If you have such a city of all plains squares, with no tile improvements, and if you ignore government bonuses, pop number 7 adds only 5 food and 5 production, and 2.5 trade. *Any* specialist is a better deal.

Lessons:

1. yes, you have 2 workers with the city size of one, but they do not both work on the first ring. When the city has size of one, you have one default worker working in the zeroth ring, which is the square the city is on, and you have one worker working on the first ring, claiming 1/6 of the resources of each square on that ring. Notice it's 1/6 of the resources, so if you have a city size of 6, you can claim full resources from 8 squares of the first ring (unless the first ring is cramped), 6 people working in 8 squares, good deal.

2. no, you don't lose a ring by turning workers into specialists. of course, those workers turned specialists no longer work in the rings. So if you have a city size of 15, and you turned 3 of them into scientists, it's the same output as a city size of 12 + 3 scientists. so far so good. however, you may lose "goods" coverage by turning workers into specialists. So if you have a city size of 8, and you turn 2 workers into specialists, your city does not get the tradable goods that reside on the second ring.

3. most of the time cramping is not an issue because you really don't want to collect resources from the 4th and 5th rings, for four reasons: a. by the time your city grows to that size, your empire is probably much weaker than the other players because of the city placement. b. POLLUTION!!! better off turning them into scientists. c. 4th and 5th rings are less efficient anyway. d. public works cost too much, and it takes longer to realize their effects in the outer rings.