Why did Jesus not want people to talk about his healing? There are numerous instances in the gospels of Jesus healing someone, and then Jesus in some form or another instructing them to keep silent about it. One example, in Matthew 9:27-31

27 As Jesus went on from there, two blind men followed him, calling out, “Have mercy on us, Son of David!”
28 When he had gone indoors, the blind men came to him, and he asked them, “Do you believe that I am able to do this?”
“Yes, Lord,” they replied.
29 Then he touched their eyes and said, “According to your faith let it be done to you”; 30 and their sight was restored. Jesus warned them sternly, “See that no one knows about this.” 31 But they went out and spread the news about him all over that region. (emphasis mine)

Why did Jesus not want them to proclaim their healing? It doesn't make sense to me, as anyone who was healed of a lifelong malady would naturally want to tell all their friends &amp; family. Was this just him making a point about how silly it would be not to share what God has done for us (e.g. the gospel) with others? Or is it something else?
When reading the gospels there seems to be two or three main problems Jesus always encountered in terms of ministry and politics. The most deadly was the jealousy and hatred of the religious leaders. Jesus often had to move away from any opportunity where they might be overly aroused and have easy access in apprehending him (Luke 20:20) Jesus seemed to manage the timing of his arrest. The second was crowd control (Matth 8:18).  As more and more flocked to Jesus the crowds became too large to effectively minister to them so he had to move away to less crowded areas and even leave to a new region to avoid crowds. The third problem is less obvious but quite clear in Jewish history, that of the zealots who wanted a Messiah to lead them in war against roman rule.

All three of these concerns might be involved in Jesus wanting to limit his fame depending on the situation , where the religious leaders and their 'spies' were, how big the crowd was and how the zealots might have used his fame for their own agenda. 

Of course there is no way of hiding a miraculous healing to those who knew the man. To those who would know he was healed he would have to explain what happened. He was not asked to 'hide' his healing, just refrain from telling people who would not already know. Jesus seems to simply want to avoid sensationalism and some political hazards. He did not want the man to broadcast his exciting experience, until perhaps much later on. Jesus managed the political landscape on which he was drawing more and more attention from crowds of people with differing motives of interest.