They typically force you to use alternative routes, and can sometimes still pick you off a few times. I like the almost WWII-ish fights you can have around each base. Dodge in and out of the main buildings, or hunker down and kill anyone foolish enough to enter your crosshairs. Lots of ways to play here. The secondary routes will probably become the main routes after a few minutes on this map.
Snipers have a tough time hitting the lower bridges without exposing themselves.
This can lead to some overcrowding down under. Friendly Fire isn't your friend down here. The map does force you to use your head in planning your jog to enemy base. That's very cool, as most maps just provide a few set routes, Chasm actually let's you vary it. The only strictly linear parts of the map are the bridges.