IOT was useful...
... in enabling me to improve my GSK exam score from 79.5% (fail), gained a few days after entry, to something slightly North of the pass mark (80%) a few days later.
I knew how to launder/iron/clean/tie a bowtie/hold a knife & fork/greet a lady/speak politely whilst drunk/stand up straight whilst drunk/eat whilst drunk/find my own way back to my room whilst drunk/find a toilet without urinating in a wardrobe whilst drunk/cope with a stonking hangover the morning after, WELL before arriving at Cranwell.
It DID teach me that people with Northern accents may sound like thickos but may not in fact be - although having lived in Lincolnshi*e for too long I remain unconvinced...