I wonder what the best way of coordination would be. Perhaps they can identify several promising lines and each player chooses one variation to calculate more deeply.
From my own experience playing (as a weak amateur), I feel I'm rarely able to think so systematically -- often ideas I discover while contemplating one line are tried in entirely different variations, so it would perhaps take some getting used to before a team can function optimally.
They would have to use a software to divide the search tree between them and collect their judgements.
I'm wondering how would a mixed team of AIs and humans fare? For example, a team of 1 AI and 4 humans against a team of similar setup. Humans could be assigned to judge parts of the search tree and their inputs aggregated by the AI.