I realise the following is a very specific question, and possibly requires a specific expertise, but research has failed to turn anything up and I'm reluctant to join another, specialist forum just to ask one question:
Those of you who have seen the Changing of the Guard ceremony (at least the one in Windsor - I assume it's the same in London) will know that at certain points the officers parade up and down in front of their men, holding their drawn swords. Reputedly this dates back to the 18th century, and was done before battle to demonstrate they weren't drunk! No idea if that's true. However, I was puzzled by the fact that with the Irish Guards they carried their sword just above the hilt, rather than by the grip. I asked a former Grenadier Guards acquaintance of mine, who confirmed this is a tradition specific to the Irish Guards, but did not know the reason for it.
I'd love to have an explaination for this seemingly rather hazardous activity - after all, the blades are sharp! - so I'm turning to the knowledgeable company here for help.