the bigger the stack the more often you can get away with betting to steal the blinds. if the blinds are 1k/2k you started with only 3k, and you sit on 100k you can be the aggressor and bet lots to take blinds, if you are at 35-45k however if you bet too often to take the blinds you will get cought and it will be counterproductive to your cause. someone will come over the top and you will be put in a tough spot. so if you are mid stack its still very wise to take blinds but only play one in nine hands roughly, then you have more of a chance to get away unnoticed. if you are small stack to steal blinds successfully you will need a tight image....you go all in two or three times someone call you for sure.