Playing from the big blind in Limit Hold Em is much different from playing from the big blind in No Limit Hold Em. The biggest difference is the frequency of defending. In No Limit Hold Em, every time a player enters the pot, he knows his whole stack can be at risk. Therefore, he is not going to want to play from the big blind with just any random hand. After all, he can lose a lot more than just calling the raise.
However, limit holdem players know the maximum amount of bets they are going to lose is small in relation to their stack size. Besides that key reason, No Limit Hold Em players can raise to any dollar amount that they choose, so they can make the big blind have to call a large amount. In Limit Hold Em, the opening raiser can only raise to double the big blinds bet. That means at $2-$4 Limit Hold Em, when a player open raises to $4 and it folds to the big blind, the big blind will only have to call $2 to play for a $7 pot. He will be getting 3.5-1 odds on a call, certainly more than enough to justify making the call with almost any two cards. This important concept shows that a player must defend his blind very often in Limit; otherwise, he is going to be losing money.
Since the big blind will always be getting 3.5-1 on a call, calling with 2-3 suited is the correct play even if the player knows the opening raiser has a hand such as AK. 2-3 is not a big enough underdog against AK to justify folding to those odds.
Players defending the big blind must beware of one key mistake. If a player always defends his big blind, only to fold to a continuation bet whenever he misses the flop then defending the big blind becomes a bad play. Why put more money into the pot just to fold whenever the hand misses the flop (which will be most of the time)? Therefore, it is imperative that a player is willing to call continuation bets with air a certain percentage of the time to make defending profitable.
Obviously then, do not defend the big blind if another bet will not be called without flopping a pair. The other time not to defend is when there is a raise and then a reraise. Then not only will the big blind have to play against 2 other players, but he will not be getting good odds to call, since he will have to call a double bet.
