Coin-flips are not restricted to pre-flop variables. If you’re holding J-Q and your opponent has 7s and 7c, you are in a pre-flop flip (er, OK — Ed). But if the flop comes 10d 9d 6h, although you missed your cards —so your flop -flip was a flop — you continue to be a flip (what, aflop-flip flop flip? Brain starting to hurt — Ed).
OK, if we all accept that there are variables (and that, if you have to gamble, the odd percentage point in advantage is welcome), then let us continue on the generalisation that a coin-flip is a situation where you have somewhere around a 50% chance of winning — that is, roughly, an even money shot. It has often been said that you can see if a player is in or out of form by whether he is winning his flips. Now, I am not sure there really is such a thing as a good flip, to be honest — but I certainly think that some are more worth taking than others. And there are also times when it’s simply necessary. If you are a serious player, then you have spent many, many hours practising and analysing, and it seems crass to have a tournament-making or -breaking decision resting on a coin-flip. However, much as I wish I could say it was, poker is not all about skill. I once read that when Chris Moneymaker won the Big Dance, he had to survive 42 coin-flips. I don’t know if that number is accurate, but it seems about right.