[Mogobu The Fool]

The cards are useful for people who do actual data mining, but what most people do is just data collection. For developing stats on individuals (data collection), the hole cards are not very useful - you won't accumulate enough of them against any one player to develop strong trends. The exception is, of course, the "regulars" that you have many hands on at your same limits - I mean many tens of thousands of hands. But for people where you have 5 or 10k hands, it's not that useful - 10k hands means 1000 showdowns, which means probably 100 showdowns per position - and remember, people play very different hands in different positions, or play the same hand differently in different positions. 100 card pairings shown is a bit weak to draw any strong conclusions, absent other factors. . . but it's plenty to make more basic assumptions.

Now, if someone were doing actual datamining - that is, mining information out of the data they collecte - the hole card info would be useful. Across that large a sample, you can develop information about the cards various segments of the population generally play, and then you can extrapolate based on classifying new individuals into those segments.