The Trade ( or hacking )
 
   Nothing hurts a player that is down a piece or two worse than trading pieces or hacking. Hacking is the senseless trade of a player to take the piece off the board but lose the same value at the same time.
   I've seen players that have a major or captain advantage and just hack the rest of the game away until the opponent has no choice but to forfeit. Other times I've seen players that are DOWN a man and hack anyways without thinking that they are hurting their own cause.
   Trading a player can be the only choice one has in a defensive situation. Suppose your spy was captured. The only way to take his Marshall is to trade. Sure you'll lose your MArshall but your opponent won't have his on the board either.
   Experienced players know that trading players IF you have the advantage is justified since you need just a 3 player advantage in order to securely defend an attack on any lane. When your opponent has bombed in a lane the magic number is just 2 players. But is this strategy a popular one or is this a "lazy" way of winning? I've always assumed that finding the flag is not my primary purpose in winning a game. I've always felt that controlling the enemies army and leaving him or her no choice but to submit is the better way to win. Finding the flag out in the open on a fluke is sometimes a cheap way to win, especially if you're down and your opponent has left his flag unprotected ( hmmmmm, subject 5 for the next War Room ?)
   A little trick I have used to reveal a "protecting" piece is to trade the front man in order to find the protector. Let's say you have a player than reveals the 5 in the front row. He may move a player behind it in order to protect it. He sits back and , like a Venus Fly Trap, waits for you to capture the 5 while nesting a 3 or 2 or even a 1 behind the 5 taking the attacking piece out. Try trading 5s in order to reveal the "protecting piece". If your enemy parks pieces behind his front row men, trade the front row men and reveal his officers, or reveal his bluff. I get lucky every once in a while as some players park their spy behind the 2, with the 2 in the front row. Put a 9 in line and trade 2s. The next move you have you should be able to "hit" the spy and catch the Venus Fly Trapper off guard. Hehe, I love that move.
   Your thoughts are next.
Thanks

I think when u trade the generals to capture the spy, it is only piece-wasting just counter with the marshall at the other side.

This is somewhat related to what Morx said but I would say another good time to trade is late in the game when you are up in the quantity of pieces you have but down in terms of the strength of your pieces.
 
This is because a certain number of their pieces are needed to gaurd against miners going to the flag. If you trade out all the pieces they have that aren't dominant then they are going to have to keep there dominate pieces near there flag instead of hunting down your pieces or clearing a path for thier miner. If they are stuck on defense then the worst you can do is a draw and alot of times you can win this if you have multiple pieces they don't know the value of.

Personally, I find the hacking routine boring, particularly if it starts right away. It can become viable, and indeed death sentence, for the player that is down.
 
I do really prefer long games wherein complex strategies are mapped out, and there is nothing quite like an elaborate scheme whereby the opponent loses a 1 or a 2 without the equivalent loss to yourself.
 
That being said, sometimes you just need to take out a Marshall, General or Colonel...