That is simply "bass ackwards". Why in the world would you spend all that time and money just to hack chunks of it out to get the track in? It is difficult enough to lay track without the scenery in the way. It isn't as if we have an army scale sized people to do the work. We have to get in there with our oversized hands.
Now it is a good idea to plan out your terrain before laying your track. Cuts, fills and bridges give a layout a much more realistic feeling, AS IF the railroad was carved through the landscape. Three railers may not take this approach as much as two railers do. It takes a lot of space to pull it off.
