From: Columbia, MD. USA
Research Benefit and Spotting are different functions that both use S&I.
Research Benefit is gained only if your S&I level is greater than all of the opposing powers S&I level. So for defensive purposes (i.e. denying your opponent a benefit) only the power with the highest level on your side counts. Multiple powers investing in it does have the benefit of increasing the chance of 1 of them leaping ahead via a breakthrough.
If an individual power gets a Research Benefit because it's S&I level is higher than all of the opponents, it only applies to the power itself and does NOT provide any benefit for allies.
Unit Spotting is directly based on simply having a level greater than 0 for S&I, and is checked for each power on the active (i.e turn taking) side individually. If UK has S&I 2, France S&I 1, Russia S&I 0, Serbia S&I 0, and Italy S&I 0, then there will be 2 checks for each CP unit to be revealed, 1st check is 2% chance and the 2nd check 1% chance.
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