Here is my input, as a lowly member, in regards to #42:
It is the calling player's responsibility to determine the bet amount of a player. If the player wants an accurate count, he must ask the dealer. If he doesn't, it is the player's fault and he must always be liable for the full amount of the call. (Maybe one exception: all-in player has some hidden chips found after.)
If the player asks the dealer for a count, it is the dealer's responsibility to provide an accurate count and the player's responsibility to make sure the dealer does an actual count. Plus, it is the betting player's responsibility to ensure that all his chips are accounted for. So each has some shared responsibility for an accurate count.
For speed of the game and simplicity, most of the time players don't need an exact count. But that determination falls on the player calling the bet.
So the player calling a bet has a choice:
1. Accept an approximation of the bet amount. In this case, it was the player's choice and any shortfall he should make up for. A gross mistake invoking rule #1 should only be something extraordinary (like hidden big denomination chips, a standard rules violation).
2. Ask the dealer for an exact count. In this case, it falls to the dealer to provide an accurate count and the betting player to make sure he isn't shorted. In this case, the player calling should always only be liable for the amount stated by the dealer, no matter what. The betting player should make a correction before the action is complete if he thinks it isn't correct.
So I think the rule should be:
Poker is a game of alert, continuous observation. It is the responsibility of all involved players to determine the correct count of any bet or call. A player may request of the dealer when it is their turn to act a physical count of another player's bet. If he then receives an incorrect count from the dealer and acts on it, the player is liable for only the stated amount, but the player who made the original bet may correct the amount stated by the dealer before the other player acts. If a player does not ask or wait for an exact physical count by the dealer before acting, the player is liable for the full amount of the bet even if it differs from any approximate or partial count given by the dealer or the other player. Any uncalled chips are pulled back by the player except in the case of an all-in.