Other than Amtrak's ridiculous chocking and securement rules - which stem from us being a "scared to hold anyone accountable for their actions" passenger railroad - the only times I've seen cars chocked sensibly is (1) when the handbrake is completely inoperative and there are no other cars to secure that are coupled to it and (2) securing cars spotted on the RIP track in a freight yard. School of thought being the car department can do ANY type of repair they wish, including repairing a defective handbrake, without unintentionally compromising securement. In my opinion, a very worthy use but only in a yard designed for such activity.
Railroading 101 Rules regarding chocking:
-If on a curve, cars get chocked on the inside rail - if for some reason the car gets shoved over the chock there is a far less chance it will derail
-if an engine is chocked, it gets chocked under the engineer's side cab window
-if engines in MU are chocked, the chocks are placed under the controlling unit's engineer's side cab window
-chock both sides of 1 wheel only
Railroading 101 Rules regarding chocking:
-If on a curve, cars get chocked on the inside rail - if for some reason the car gets shoved over the chock there is a far less chance it will derail
-if an engine is chocked, it gets chocked under the engineer's side cab window
-if engines in MU are chocked, the chocks are placed under the controlling unit's engineer's side cab window
-chock both sides of 1 wheel only