I agree with henry6. There are too many rules already, we don't need more.
As an example, we had a situtation in dark territory where a surfacing crew was giving up their track occupancy. A train was waiting at the red flag ready to go as soon as the equipment was in the clear and the foreman released them.
The foreman got the equipment into the side track, released the train and went into the depot.
You can see this coming can't you?
The next thing the foreman knows, the train is in emergency heading into the side track on top of his equipment. A fair amout of equipment damage but no injuries or derailment.
During the review, investigation and analysis of the incident there was a lot of discussion about writing a new rule. (The proposed rule eventually put in place was the one noted above by cptrainman) Aside from the expected discsipline being issued, this new rule was pretty much the only other action taken and everyone felt they had "solved the problem".
I argued against this new rule on the basis that there were already at least 6 other rules in place which dealt with the proper position of main line swithces which were ignored and adding this rule would not have changed this situation.