Hmm. Under ideal conditions, basic RT (the 0.66 rate that we'd be offering) should increase the effective yield of a given territory size by 10%.Rotating tactics offers her far less benefit than you believe it to. And it's also far less guaranteed than the value of territory.
Edit: These values are in error. Corrected figures in a post below.
Guesstimated size of their territory is in the 250 to 350 range, though this implies it might be lower, so perhaps down to as little as 200. 10% of that means between +20 and +35 cubes per month, on average.
However, since they have to deal with poaching, they can't actually make use of the full RT bonus. Effectively, they'd be using the RT bonus to absorb the losses of being unable to fully exploit the territory.
Suppose, for example, they can only effectively use 6 points of DS for RT, with the other 4 points being abused by poachers. In that case their gain is only 5%, giving them between +10 and +18 cubes per month, subject to the whims of the poachers.
So any amount of Tokyo territory — say a block of size 50 (1 million population) — would give them more cubes in a stable fashion (20 cubes if the native population is 50%, and there's a 10% overage to cover spirals and such) than what they could get from the RT approach. Size 100 territory block would give them more cubes than RT would give them even without the poacher interference.
And even a size 100 territory block is not that huge of a demand, given that Tokyo has a total harvest capacity of almost 1900 cubes. However it's probably larger than they could maintain, since it would require dropping their local forces by a pretty significant amount in order to staff it. It's also pretty significant at the political level, given their existing size, so I rather doubt it would go higher than that. 50 is probably a decent target; possibly less if we get an otherwise unoccupied region available for them.
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