Those pesky stud games. In addition to requiring more from players in terms of attention, memory and reading ability, they also have one more round of betting than flop games. Hold'em and Omaha have four rounds of betting — pre-flop, flop, turn and river. Stud games have five rounds of betting (third through seventh streets) and to make things a bit more interesting, the extra street is a big-bet street, making for two small-bet streets and three big-bet streets. Getting to the river is more expensive in the stud games than it is in flop games.
There are numerous impacts of this one extra round of betting, some subtle and some game-specific. Straight away, it means that by fifth street, with five-sevenths of his final hand, a player is put to a decision whether to go all the way to the river or fold. Notice the difference from hold'em or Omaha, where a player knows five-sevenths of his hand on the flop, a small-bet street. Players in flop games can often get to the turn, to see their sixth card, by putting in one small bet. The difference may not seem like much, but consider that players often fold in hold'em or Omaha if the flop is raised to two or more bets. That's the equivalent of a single bet in the stud games on fifth street.
Conventional wisdom dictates that if your hand is good enough to continue from fifth street to sixth street, then absent a particularly brutal sixth street that completely misses you and significantly improves your opponent's board, you pretty much have to come again from sixth street to seventh street. A player who makes a decision to put in a big bet on fifth street is really deciding to put in a total of at least two big bets, and possibly three big bets to get to showdown. As a result, players who decide to play after fifth street generally need to have a made hand or a strong draw, absent a stone bluff. (Some might say that, in the stud games, if your hand hasn't improved by fourth street, you should generally fold. That's not the worst advice for beginners, but playing that tightly should generally be reserved only for the lowest-limit cash games and some tournament situations. With a strong starting hand, paying one small bet to see fifth street after catching a brick on fourth street isn't always a horrible play.)
It's not all bad news, though; the extra big street also allows a player who has the best of it to put increased pressure on his opponents. For example, in a pot on fifth street in stud hi/lo, if the boards show one player with a made low or an excellent low draw against one or more who appear to be going high, it's time for the player with the low hand to juice the pot. Not only is he freerolling the high for the next two streets after fifth street, but he may very well find himself in the enviable position of being between two players who both think they have the best high hand. Even if the player with the low doesn't make the winning high hand, he's able to increase his half of the pot by getting money in as soon as the streets get big. This can also be done on sixth streets and seventh streets, but by waiting that long the player with the low may be missing out on bets.
Razz provides another excellent example of using stud's big-street betting structure to a player's advantage. A situation that continuously presents itself in razz is one in which Player A has a hand such as / against Player B's board of (x-x) / . With the lower board, Player B has first action and will often bet here, thinking that his ten-nine is the better hand against Player A's king-high. Yet the numbers show that even when Player B has ace-deuce in the hole, he's a 62-to-38 underdog against Player A's hand. This is because Player A will improve to a better hand then ten-nine with any deuce, five, seven, eight, nine or ten, and even if Player B improves, he will only be improving to at best a nine-five — a hand Player A still beats with any deuce, five, seven or eight. The right play for Player A if Player B bets into him on fifth street is to raise and never stop raising.
Again, this situation is not so different than flopping a huge draw in hold'em or Omaha. However, because of the difference in the size of the bets between a flop game (small bets on the flop) and a stud game (big bets on fifth street), more pressure can be applied to an opponent. It's like raising the turn in hold'em or Omaha, only in those games the player only has to call one bet to get to the river.
The truth is that at intermediate and advanced levels of play, most stud hands end at fifth street absent two players with very strong hands and/or draws. This is because disciplined stud, stud hi/lo and razz players know that chasing beyond fifth street is too expensive to justify. Take a tip from these players and think about how much it will cost to get to the river the next time you're at fifth street of a stud variant and considering a marginal call. Most of the time, it's just not worth it.