[thejeff]

Just pull the troops back to the rear of the field and put them on hold and attack.

It depends on what troops you have and what you expect them to have.

I've been playing Man lately, so I'm likely to have serious missile superiority. I'm fighting Jotuns so I'm not likely to break through the gate easily. Solution: let them come out, swarm them with smaller troops and pound them with arrows. If you've got better artillery mages, the same strategy can work.

If you've got better troops who can break through the gate defenders and get inside, do that.