WHFB for Dummies: The Art of Fleeing
In WHFB you are able to react in a few different ways when an enemy charges you. You can hold, which means you'll receive the full brunt of the attack, you can stand and shoot, which is basically holding, but hopefully killing a couple enemies first, or you can run for the hills. Most units don't want to choose that last option, it's risky, and it means you are limited in what you can do in your following turn, but that's not to say it should be ignored. Units of fast cavalry have the Feigned Flight rule, which allows them to move and shoot as normal, should they successfully reform after a charge. This is huge and allows fast cavalry to constantly harass enemies with little fear of reprisal.
So why do we flee? There are two answers, the first is obviously to run away from a unit which will undoubtedly annihilate your own, the other reason is to put the enemy at a disadvantage.
Lets take a look at this scenario. We have a block of steadfast Swordsmen, which will hold for a long time and tie you up, obviously you don't want that to happen, so we need to be sneaky to remove their steadfast. So to counter them, we put a nice juicy target in front of them, in the form of Glade Riders.
The enemy seeing the opportunity to get some easy victory points takes the bait and charges your Glade Riders, who subsequently flee. The opponent moves up 5" and ends up just inside the woods. If you manage to pull the enemy where most of them are in the woods, you'll also remove their steadfast and then they are prime to get charged by something in your army that can cut them apart and chase them down.
Hurray, the Glade Riders live to see another day!
Here is another scenario, similar to one I found myself in not too long ago playing against my friend's Wood Elves. I have a block of infantry, who seem to have gotten themselves surrounded by various Wood Elf threats. Knowing that the Halberdiers can't handle fighting the Dryads in the woods, and not particularly wanting to continue being a pincushion, for the Wood Elf shooting, the Halberdiers have to get into combat somewhere. They have a few options, charge the Scouts, the Glade Riders or the Dryads.
The Empire player isn't dumb, they know that charging the Dryads in the woods means he will loose steadfast and be slaughtered, so he declares a charge on the Scouts, trying to get the furthest away from the Dryads as possible. The Scouts flee. Frustrated, the Empire player redirects into the Glade Riders, if he can kill them and overrun, he will be out of the front arch of the Dryads and thus safe from reprisal. The Glade Riders flee. After rolling the dice, the Empire player scores a 3 and 4, moving forward 4", accomplishing nothing.
Using flee to set up the enemy and bait them is one of the more advanced strategies in WHFB. Fortunately, not all armies can take advantage of it as well as the Wood Elves, but no matter who you face, if there are Fast Cavalry involved, this is something you'll have to watch out for.