I get the impression that the core problem in this scheduling and OTP struggle is that in reality significantly more that 50% of the operations on many freight lines are what in airline dispatching parlance would be characterized as "Irregular Operations". Given the limited track resources for the demand that is placed on them together with essentially very loosy-goosy operating plan, if there is one at all, is it surprising that it is hard to keep anything on schedule according to what in reality is a non-existent plan? None of this is really accidental. It is a calculated tradeoff.