Rather the opposite is true, it prolonged his suffering and increased the risk that he could have been killed! Let's not forget, long ago, in early 2007, Hamas negotiated with Israel through Egyptian mediators. At that time, the demand was to free 1300 prisoners. Since this was a demand open to negotiations, a deal about 1000 prisoners certainly was possible. And actually, most of the world believed at that time that an exchange was just around the corner. Still, the Israeli government decided not to approve the almost finished deal. Of course, it's debatable if there were good reasons for that, but there's no good reason to claim that "Israeli stubborness saved Shalit." The facts show that this simply isn't true.
U.S. says it killed 10 AQAP Islamist militants in four air strikes in Yemen since April 23 (Reuters)
from the article: Israeli stubbornness saved Shalit, but at a price