Permit me to say, but what is the point of knife running?
Knife running is when you run (usually sprint) with your knife (a nade works just as well, by the way) because it's a lot faster than running/sprinting with a big assault rifle (but some guns like uzis don't slow you down that much).
Anyway, strategies, but only for a few maps.
Here is a good all round pointer: ALWAYS EITHER BE RUSHING THE ENEMY FLAG, LAYING MINES TO DEFEND YOUR FLAG, OR CAMPING A FEW FEET AWAY FROM YOUR FLAG! If you're not doing one of those three things, your not helping your team.
Junk Flea: NADE!!! No matter what you do, always nade the are near the flag before you go over there!!You'll als get a bunch of kills. Ummmm, what else >_> ........
OH YEAH!!! If your on alpha, go to the other side down your right and come back the same way you went there, but when you're dropping back, drop a nade where,well.....You know that big, red crate and the intersection shaped like this on the side of the Bravo team?
| ______________
| |
Big Red Crate|
B
A
"A" is where the flight of stairs to go up starts from the Bravo side, and B is where you drop the nade.After you drop the nade, run into the building, and run out straight into the flag are (the running into building and sprinting to goal are both done with knife or nade only!)
If your on Bravo, go to the enmy flag via your left side, get the flag, run behind those water tower thingies, run out of them after running towards your base behind them, and drop a nade at the choke point betweenn the tank and the fence or a few feet after. After that, take a right ( you will be next to a fence) and enter your base, then run straight into the goal area.
Snow Valley: No matter which side you're on, take the underground tunnels to the enemy base, and if you have a sniper rifle, take up a sniping spot (on the hill for the alpha base and on the red towers for the bravo one) and wreak havoc. If you don't have a sniper, just take the flag, and run towards your base.
Pump Jack: The only strategy for this map is to constantly rush blindly and nade like in Junk Flea, but there is a really clever strategy to help a friendly flag-holder.
As soon as a friendly gets the flag and sprints away, SPRINT RIGHT AFTER HIM! The walkways in that level are so narrow that if you run right behind him, YOU CAN ACTUALLY ACT AS A HUMAN SHIELD AND ABSORBS DAMAGE!
Those are the only maps I play CTF on, sorry.