There's a difference between a 'TV-pro', the type of 'pro' that appears on the WSOP, and a real pro poker player, someone that makes their living off profits at the table. These aren't mutually exclusive (Phil Ivey, for example), but it seems that your impression of pro poker players is of the 'TV-pro' variety.

Players who rely on winnings for their livelihood do meet the author's description. In particular, for online poker players, the # of hands per year can total in the millions, and you can get pretty specific about the types of strategies/decisions that will alter your bottom line. I played poker online pretty seriously (and profitably) for about 2 years, logging over a million hands, and I definitely did no self-promotion.

Check http://www.pokertableratings.com/, a site that logs all hands played at the major poker websites. A major statistic is BB/100 (big blinds won per 100 hands), which is an oft used metric for profitability. The online poker community has a very good idea of the expected BB/100 at various skill levels/stakes, and the associated variance - it's very much a 'science'. The impression of self-promotion that you have is an unfortunate result of commercialized poker TV.