[judk]

As a team, they get two guesses. So those two guesses have to cover the space of possibilities, and a guess has to be of a form such that seeing one's own coin implies the guessed value of the hidden coin. (So, "Bob has heads" is not a valid strategy guess. A strategy guess has to describe the state of both coins, so each perskon's strategy guess cannot include two pairs of the form "mine=X, other=H " and also "mine=X, other=T".

This seems a bit awkward, but information theory "guessing" is called "error correction", and parity-checking is the simplest and by far most common strategy. (Advanced algorithms are fancier multidimensional parity computations) So, their two guesses are "same" and "different" (aka parity 0 and 1). A and B each are allocated one of the two strategyGuesses, and translate observedCoin+strategyGuess=hiddenCoinGuess