07-30-2010, 09:13 AM
Standing freight cars are not earning cash. Railroads try very hard to "keep them moving" either to/from a customer, or back to the home road so they don't have to pay per diem. So, in a way, yes a full freight yard would imply a busy (or gridlocked) railroad... but the Yardmaster would trying his darndest to get those standing cars out of his yard and moving again.
-Dave