Sadly I am a total racist. - but only in my own country - England. I make no excuses. I am Anglo Saxon & am proud of my heritage. My Grandfather was the RSM of the Vth Inniskining Dragoon Guards during both the Boer War & the 1st World War. He was awarded both the MC & the DSM.
Oh dear, Sam! I'll leave others to comment on whether or not you are a racist, and also respond to your intemperate personal outburst against named officers, and content myself with helping you sort out your family tree.
Firstly, there has never been a regiment named the Vth Inniskining Dragoon Guards. There was a regiment named the 5th Inniskilling Dragoon Guards, formed from the amalgamation of the 5th and 6th Dragoons, but this was not until 1927, long after the periods of service you mention. Furthermore, in view of your burning desire to be regarded as English, please note that the "Skins" as they were known had all their origins in Ireland!
Secondly, assuming that by DSM you mean the Distinguished Service Medal, you should be aware that this was instituted in 1914 for award predominantly to naval personnel rated Chief Petty Officer and below, whlist the DSC or Distinguished Service Cross was awarded to commissioned officers and warrant officers until 1993, when the DSC was awarded to service personnel of all ranks and ratings. I appreciate that it would not have been impossible for your grandfather (assuming that he was not a walt) to have been awarded the DSM, but it seems much more likely that he was awarded the DCM or Distinguished Conduct Medal, which actually rates higher than the DSM, or its army equivalent the MM or Military Medal.
So, once you have considered that you really should remove the extraordinary personal remarks, I suggest that it would be better employed contacting either the National Records Office or the Dragoon Guards Museum in York to find out more accurate info about your very interesting sounding grandparent.
I certainly hated ignorant Scot's who would always try to shout you down.
Oh double dear, Sam, who is being ignorant now?
Jack