I wish the best of luck to all those in a quest for flawless operation, you're gonna' need it!
In my dateless past, when I actually had an OPERATING railroad (my current S scale lies dormant in a non-functional state... shame on me), I would ocassionally have a derail during an operating session. I learned it was fun to treat the derail as part of an operational situation. If it was minor (a set of wheels or a truck off), it caused about a 1/2 hour (fast time) delay. If not so minor (two cars, or an engine, whatever) then more time needed to "rerail it". In the meantime, other traffic had to make do and come up with other options on how to deal with it. (Never had catastrophic derails.) However, before I started doing the railroading thing for a living, I liked the "drama" of railroading and incorporated aspects of it into my operational schemes, including devising methods for random engine failures, and such as that. Doing so added a new element when climbing the ruling grade with a tonnage train, and the time comes up to open the "Situational Card"... and it said I just lost a unit in the consist, thus my train would "lay down" and not make the grade as is. Now I had to double the mountain, and deal with reduced tonnage ability as I finished the run of that particular train. (Or, instead of doubling, if another train was behind me, it's power could cut-off and come up behind and give me a shove. Depended on what the Dispatcher decided!) Of course, there are many, many model railroaders that aren't into replicating "operation" in miniature... and thus the above would be of little interest to them. To me, though, a layout has to have good "purpose" and the situations faced in railroading incorporated into its operational scheme of things as well. I learned in the mid-70's that doing so added immensely to the enjoyment of model railroading for me. Operation is a "freebie"... doesn't cost you an arm and a leg... but can really kick it up a notch in regards to the fun factor. The key to such was finding a good balance so that it is believeable and not a travesty of day-to-day operations found on the prototype. Whatever your pursuit or reward in model RR... have fun! Andre Ming
