John, since I was not aware of the circumstances surrounding these accidents, for anyone interested in your comments, the Cahir accident was discussed on the site here
http://irishrailwaymodeller.com/showthread.php/829-Cahir-crash-1955
The report into the GSR accident at Straboe during the Emergency seems to confirm your assertions that there was widespread non-observance of safe practices by drivers and guards, contributed to in minor part by equipment shortages including oil for train lighting
http://www.railwaysarchive.co.uk/documents/DIE_Straboe1944.pdf
The accident at Dundrum was attributable to an signaling error by the signal man and failure to warn more then one train of a potential obstruction on the line. Once again in darkness with a contributory rear lighting failure on the first train