Anyway, I was in Las Vegas last weekend and hung out with a Black Jack pro. His basic strategy was to find 2 deck black jack tables, which would give him enough time to count cards and generate an advantage. If they reshuffled too early, say after 52 cards, he couldn't make money, and this was part discretionary, part casino rule.
I won't give away all his secrets, but the bottom line is that it didn't seem worth it to me. As a job, not an avocation, it didn't seem fun, or even really well paying. The basic card counting part of the job is pretty mechanical and after repetition rather easy. Most importantly, he had a very interesting time with the dealers. Basically, you want them to know and like you, but just a little. Too much, and they will catch on to your game, too little and they won't do you any favors.
As they have a lot of discretion, and you are hoping to make say $300 off any on dealer, which in the context of their weekend is not a lot. Thus, they might choose to deal to you with only 25 cards left in the shoe, if they like you, whereas if they don't like you they will reshuffle after 50 cards. A great salesman is one who can make customers like them so much they don't mind paying a little extra, and don't like to even think about what is happening (like when dupes don't care their partner is using them because they are so adorable). Smarts are necessary to make this happen, but to make it a really valuable strategy you need the ability to make the opportunity cost seem a lot smaller than it is.