As a man that has overcast in to many a snag, the best thing I can recommend to do is to point the rod directly towards the snag, tighten up the clutch and walk backwards keeping the rod in line until the hooklink or line breaks (or you pull in the tree your attached to). It should go at one of the knots, worse case at the reel, but your rod should stay in one piece.
Be careful of flying leads/feeders heading back your way though!
Wrap a towel or rag around your wrist and grab the line just beyond the rod tip, that way you avoid breaking off at the reel, the worst place it can go. When you do it this way you tend to break the mainline at the hooklink/mainline join
Even better! Can't believe I didn't think of doing that before.
Thanks.