It's definitely a negative way of describing someone who doesn't make a decision, who sits back and says, " Well, maybe yes, maybe no." " To straddle the fence" is more neutral;that is, it doesn't necessarily mean you're criticizing the person.
这绝对是一种消极的方式来描述一个不做决定的人，他坐下来说， “好吧，也许是，也许不是。 ” “跨过栅栏” 更中性；也就是说，它不一定意思是你在批评这个人。