Timing is key, as well as teem coordination. You must have people still on defense as well as people willing to cooperate with the rush.

The BIGGEST problem: people unwilling to participate in the rush. This is the demise of all rushes, actually. Don't be afraid to try something new.

Also, the beacon in tunnel trick on Field is not a viable strategy. It's too tricky to be effective and leaves your team vulnerable. Timing is so important and is sooo hard to get it right. I wouldn't recommend getting a team of people to do this unless you have plenty of people on the server.