A couple months back (over here) I started looking at God's "policy of communication" as taught in the Bible. That is, does God promise to communicate his will for our individual lives regularly outside of the words of the Bible? My answer is "no" and I began looking at verses that Christians might think supports an answer of "yes." Time to pick up that trail and examine another verse.
Gideon said to God, “If you will save Israel by my hand as you have promised— look, I will place a wool fleece on the threshing floor. If there is dew only on the fleece and all the ground is dry, then I will know that you will save Israel by my hand, as you said.” And that is what happened. Gideon rose early the next day; he squeezed the fleece and wrung out the dew—a bowlful of water. Then Gideon said to God, “Do not be angry with me. Let me make just one more request. Allow me one more test with the fleece, but this time make the fleece dry and let the ground be covered with dew.” That night God did so. Only the fleece was dry; all the ground was covered with dew. (Judges 6:36-40)
A Christian might use this account to validate an approach for finding God's will that relies on this sort of thought process, i.e. "if X happens it means you want me to do this, but if Y happens you want me to do that." But can this passage of Scripture really be used to be establish this sort of practise as normative? I don't think so!
First of all the passage is part of a historical narrative, it is recording what happened, not giving instruction for what believers ought to do. The sort of thinking Gideon displays in this passage was common to peoples of the Ancient Near East but no instructional passages in Scripture actually prescribe it. It seems then that God does not condone this practise but he did mercifully respond to Gideon's use of it at this particular point in history.
In addition, Gideon's resquest seems to require supernatural power to accomplish which would be more telling of God's involvement, as opposed to a more mundane conditional like, "if Mary smiles at me you want me to marry her, if not you want me to never talk to her again." For these reasons then, this passage does not legitimise using the outcome of circumstances to discern God's will for our lives.